Scientist reveals what the earth has been trying to do
Keith S. Taber
Seismology – the study of the earth letting off steam? (Image by ELG21 from Pixabay)
"the earth has one objective, it has had one objective for four and half billion years, and that's…"
In our time
'In Our Time' is an often fascinating radio programme (and podcast) where Melvyn Bragg gets three scholars from a field to explain some topic to a general audience.
Imagine young Melvyn interrupting a physics teacher's careful exposition of why pV = 1/3nmc2 by asking how the gas molecules came to be moving in the first place.
I am not sure if the reason that I sometimes find the science episodes seem a little less erudite than those in the the other categories is:
a) Melvyn is more of an arts person, so operates at a different level in different topics;
b) I am more of a science person, so more likely to be impressed by learning new things in non-science topics; and to spot simplifications, over-generalisations, and so forth, in science topics.
c) A focus in recent years on the importance of the public understanding of science and science communication means that scientists may (often, not always) be better prepared and skilled at pitching difficult topics for a general audience.
d) Topics from subjects like history and literature are easier to talk about to a general audience than many science topics which are often highly conceptual and technical.
Anyway, today I did learn something from the episode on seismology ("Melvyn Bragg and guests discuss how the study of earthquakes helps reveal Earth's secrets [sic]"). I was told what the earth had been up to for the last four and half billion years…
Seismology: Where does this energy come from?
Quite early in the discussion Melvyn (sorry, The Lord Bragg CH – but he is so familiar from his broadcasts over the years that he seems like an old friend) interjected when Dr James Hammond (Reader in Geophysics at Birkbeck, University of London) was talking about forces involved in plate tectonics to ask "Where does this energy come from?". To this, Dr Hammond replied,
"The whole thing that drives the whole caboose?
It comes from plate tectonics. So, essentially the earth has one objective, it has had one objective for four and half billion years, and that's to cool down. We're [on] a big lump of rock floating in space, and it's got all this primordial energy, so we are going right back here, there's all this primordial energy from the the material coming together, and it's trying to cool down."
Dr James Hammond talking on 'In Our Time' 1
My immediate response, was that this was teleology – seeing purpose in nature. But actually, this might be better described as anthropomorphism. This explanation presents the earth as being the kind of agent that has an objective, and which can act in the world to work towards goals. That is, like a human:
Of course, in scientific terms, the earth has no such objective, and it is not trying to do anything as it is inanimate. Basic thermodynamics suggests that an object (e.g., the earth) that is hotter than its surroundings will cool down as it will radiate heat faster than it absorbs it. 2 (Of course, the sun is hotter than the earth – but that's a rather minority component of the earth's surroundings, even if in some ways a very significant one.) Hot objects tend to cool down, unless they have an active mechanism to maintain their temperature above their ambient backgrounds (such as 'warm-blooded' creatures). 3
So, in scientific terms, this explanation might be seen as flawed – indeed as reflecting an alternative conception of similar kind as when students explain evolutionary adaptations in terms of organisms trying to meet some need (e.g., The brain thinks: grow more fur), or explain chemical processes in terms of atoms seeking to meet a need by filling their electron shells (e.g., Chlorine atoms share electrons to fill in their shells).
Does Dr Hammond really believe this account?
Does Dr Hammond really think the earth has an objective that it actively seeks to meet? I very much doubt it. This was clearly rhetorical language adopting tropes seen as appropriate to meet the needs of the context (a general audience, a radio programme with no visuals to support explanations). In particular, he was in full flow when he was suddenly interrupted by Melvin, a bit like the annoying child who interrupts the teacher's carefully prepared presentation by asking 'but why's that?' about something it had been assumed all present would take for granted.
Imagine the biology teacher trying to discuss cellular metabolism when young Melvin asks 'but where did the sugar come from?'; or the chemistry teacher discussing the mechanism of a substitution reaction when young Melvin asks why we are assuming tetrahedral geometry around the carbon centre of interest; or young Melvyn interrupting a physics teacher's careful exposition of why pV = 1/3nmc2 by asking how the gas molecules came to be moving in the first place.
Of course, part of Melvin's job in chairing the programme IS to act as the child who does not understand something being taken for granted and not explained, so vicariously supporting the listener without specialist background in that week's topic.
Effective communication versus accurate communication?
Science teachers and communicators have to sometimes use ploys to 'make the unfamiliar familiar'. One common ploy is to employ an anthropomorphic narrative as people readily relate to the human experience of having goals and acting to meet needs and desires. Locating difficult ideas within such a 'story' framework is known to often make such ideas more accessible. Does this gain balance the potential to mislead people into thinking they have been given a scientific account? In general, such ploys are perhaps best used only as introductions to a difficult topic, introductions which are then quickly followed up by more technical accounts that better match the scientific narrative (Taber & Watts, 2000).
Clearly, that is more feasible when the teacher or communicator has the opportunity for a more extensive engagement with an audience, so that understanding can be built up and developed over time. I imagine Dr Hammond was briefed that he had just a few minutes to get across his specific points in this phase of the programme, only to then find he was interrupted and asked to address additional background material.
As a scientist, the notion of the earth spending billions of years trying to cool down grates as it reflects pre-scientific thinking about nature and acts as a pseudo-explanation (something which has the form of an explanation, but little substance).
As cooling is a very familiar everyday phenomena, I wondered if a basic response that would avoid anthropomorphism might have served, e.g.,
When the earth formed, it was very much hotter than today, and, as it was hotter than its surroundings, it has been slowly cooling ever since by radiating energy into space. Material inside the earth may be hot enough to be liquid, or – where solid – be plastic enough to be deformed. The surface is now much cooler than it was, but inside the earth it is still very hot, and radioactive processes continue to heat materials inside the earth. We can understand seismic events as driven by the ways heat is being transferred from deep inside the earth.
However, just because I am a scientist, I am also less well-placed to know how effective this might have been for listeners without a strong science background – who may well have warmed [sic] to the earth striving to cool.
Dr Hammond had to react instantly (like a school teacher often has to) and make a quick call based on his best understanding of the likely audience. That is one of the difference between teaching (or being interviewed by Melvin) and simply giving a prepared lecture.
1 Speech often naturally has repetitions, and markers of emphasis, and hesitations that seem perfectly natural when heard, but which do not match written language conventions. I have slightly tidied what I transcribed from:
"The whole thing that drives the whole caboose? It comes from plate tectonics, right. So, essentially the earth, right, has one objective, it has had one objective for four and half billion years, and that's to cool down. Right, we're a big lump of rock floating in space, and it's got all this primordial energy, so we are going right back here, there's all this primordial energy from, from the the material coming together,4 and it's trying to cool down."
2 In simple terms, the hotter an object is, the greater the rate at which it radiates.
The hotter the environment is, the more intense the radiation incident on the object and the more energy it will absorb.
Ultimately, in an undisturbed, closed system everything will reach thermal equilibrium (the same temperature). Our object still radiates energy, but at the same rate as it absorbs it from the environment so there is no net heat flow.
3 Historically, the earth's cooling was an issue of some scientific controversy, after Lord Kelvin (William Thomson) calculated that if the earth was cooling at the rate his models suggested for a body of its mass, then this was cooling much too rapid for the kind of timescales that were thought to be needed for life to have evolved on earth.
4 This is referring to the idea that the earth was formed by the coming together of material (e.g., space debris from a supernova) by its mutual gravitational attraction. Before this happens the material can be considered to be in a state of high gravitational potential energy. As the material is accelerated together it acquires kinetic energy (as the potential energy reduces), and then when the material collides inelastically it forms a large mass of material with high internal energy (relating to the kinetic and potential energy of the molecules and ions at the submicroscopic level) reflected in a high temperature.
Should I pay a magazine to write a feature article about one of my book reviews?
Keith S. Taber
Dear Chris Temple
Thank you or your message with the subject 'Inquiry – Making sense of a pedagogic text', but I am a retired academic, and so do not have a publicity budget to pay you to do a feature on my research.
In any case, the publication you have selected, 'Making sense of a pedagogic text', as suitable for discussion in a feature article, presumably because [you want me to think that] you see particular merit in it, seems an odd choice, as it is an essay review of a text book. So, I immediately ask, how much thought and effort went into your selecting this article? How much of it did you read [i.e., have you read any of it?] before you decided you wanted to take up some of my time so you could "speak with you concerning your work on the Making sense of a pedagogic text paper". When I was teaching, how would I have responded to a student who wanted to have a supervision on a text, but had not themselves spent time reading it first?
However, I see from 'Linked-in'* that you consider yourself "a Project Manager who strives on increasing new business and profit to companies through new sales and fresh thinking technical marketing strategies", so I suspect there is some 'cunning plan' (some fresh thinking technical marketing strategy) behind your selection of a book review as a target for enticing me me to spend some of my pension to help your company profit. Perhaps you do have some basis for selecting this work as being suitable for the 'feature' treatment in your magazine?
Perhaps you have recognised the deep insight and carefully honed judgement I apply in the review?
Perhaps you recognised how I have managed to apply pedagogic principles to the analysis of a book about pedagogy? (Clever, those academics.)
Perhaps you agree that the textbook concerned offers an approach overly focused on one factor, and that my review is crucial to offer readers of the textbook a more balanced appreciation of the field?
Or perhaps you especially like book reviews, as I quickly found that you had also invited a Prof. Julie Crupples to have one of her book reviews featured in the magazine.
Or perhaps you, or some 'bot' you employ, has simply identified the name of a recent publication that can be associated with a name and email address. That would explain the fresh thinking/bizarre choice.
As you offer no justification for the unlikely selection, I am left to suspect that no more thought went into the choice of this publication as the basis of a feature article in your magazine than all those invitations I get asking me to write or speak on nanotechnology, virology, gynaecology, psychiatry and all the rest – which seem to be based on no more that I am someone who has published something or other, on some topic or other, somewhere on the web.
So, that raises the question of why you would not want me to share the content of your email (and so let others know about your magazine and the PR service you offer). The only obvious reason would be that you would like recipients to feel they have been specially chosen. Like most of the weakly targeted scam emails that come my way, it is clear that the vast majority of recipients will dismiss them as irrelevant, but that does not matter as long as
(a) a very small proportion find the invitation convincing and
(b) the company engages in blanket emails so that a, say, 0.01% hit rate brings in enough sales.
(* I see that you have posted a link to a video that talks about the need for social value, ethics and responsibility in business. Hm.)
If there are academics tempted to pay you for this service, they should consider:
will this count for my publications list for appointments/tenure/promotions?
clearly, no
is this the kind of publication I myself would go to to read about research?
if they know what they are doing, clearly no
is this a publication which would point me (and therefore others) to the most significant new research in my field or other fields of interest?
only when the authors of that research happen to have paid to be featured, so at best it is pot luck there, and arguably the most significant work is already getting attention because it is recognised as such in its field, and so is less likely to have authors prepared to pay out for publicity
– {I hope this does not mean you have selected my article because you think it is so insignificant that no one is going to pay it any attention otherwise!}
will this increase my research impact?
only if the general public, relevant professions, and policy makers, think this is something they should spent time reading to find out about the most important research – so, very unlikely that those in these groups who would be motivated to read about research would also be ignorant enough to think a 'pay to be featured' magazine is likely to be a good place to get a balanced view of the most significant new studies.
I would question the judgement of those academics who think this would be a good use of their time and money.
In summary then, this seems a dubious publication, with a very dubious marketing policy, that I would suggest serious scholars should avoid. I hope that clearly responds to your enquiry.
Specimens of two different types of natural 'engines'. Portrait of Sir Kenelm Digby, 1603-65 (Anthony van Dyck: From Wikimedia Commons, the free media repository)
In this post I discuss a historical scientific analogy used to discuss the distinction between animals and plants. The analogy was used in a book which is said to be the first major work of philosophy published in the English language, written by one of the founders of The Royal Society of London for Improving Natural Knowledge ('The Royal Society'), Sir Kenelm Digby.
Why take interest in an out-of-date analogy?
It is quite easy to criticise some of the ideas of early modern scientists in the light of current scientific knowledge. Digby had some ideas which seem quite bizarre to today's reader, but perhaps some of today's canonical scientific ideas, and especially more speculative theories being actively proposed, may seem equally ill-informed in a few centuries time!
There is a value in considering historical scientific ideas, in part because they help us understand a little about the path that scientists took towards current scientific thinking. This might be valuable in avoiding the 'rhetoric of conclusions', where well-accepted ideas become so familiar that we come to take them for granted, and fail to appreciate the ways in which such ideas often came to be accepted in the face of competing notions and mixed experimental evidence.
For the science educator there are added benefits. It reminds us that highly intelligent and well motivated scholars, without the value of the body of scientific discourse and evidence available today, might sensibly come up with ideas that seem today ill-conceived, sometimes convoluted, and perhaps even foolish. That is useful to bear in mind when our students fail to immediately understand the science they are taught and present with alternative conceptions that may seem illogical or fantastic to the teacher. Insight into the thought of others can help us consider how to shift their thinking and so can make us better teachers.
Analogies are used in teaching and in science communication to help 'make the unfamiliar familiar', to show someone that something they do not (yet) know about is actually, in some sense at least, a bit like something they are already familiar with. In an analogy, there is a mapping between some aspect(s) of the structure of the target ideas and the structure of the familiar phenomenon or idea being offered as an analogue. Such teaching analogies can be useful to the extent that someone is indeed highly familiar with the 'analogue' (and more so than with the target knowledge being communicated); that there is a helpful mapping across between the analogue and the target; and that comparison is clearly explained (making clear which features of the analogue are relevant, and how).
Digby presents his analogy for considering the difference between plants and animals in his 'Discourse on Bodies', the first part of his comprehensive text known as his 'Two Discourses' completed in 1644, and in which he sets out something of a system of the world.1 Although, to a modern scientific mind, many of Digby's ideas seem odd, and his complex schemes sometimes feel rather forced, he shared the modern scientific commitment that natural phenomena should be explained in terms of natural causes and mechanisms. (That is certainly not to suggest he was an atheist, as he was a committed Roman Catholic, but he assumed that nature had been set up to work without 'occult' influences.)
Before introducing an analogy between types of living things and types of engines, Digby had already prepared his readers by using the term 'engine' metaphorically to refer to living things. He did this after making a distinction between matter dug out of the ground as a single material, and other specimens which although highly compacted into single bodies of material clearly comprised of "differing parts" that did not work together to carry out any function, and seemed to have come together by "chance and by accident"; and where, unlike in living things (where removed parts tended to stop functioning), the separate parts could be "severed from [one] another" without destroying any underlying harmonic whole. He contrasted these accidental complexes with,
"other bodies in which this manifest and notable difference of parts, carries with it such subordination of one of them unto another, as we cannot doubt but that nature made such engines (if so I may call them) by design; and intended that this variety should be in one thing; whole unity and being what it is, should depend of the harmony of the several differing parts, and should be destroyed by their separation".
Digby emphasising the non-accidental structure of living things (language slightly tidied for a modern reader).
Digby was writing long before Charles Darwin's work, and accepted the then widely shared idea that there was design in nature. Today this would be seen as teleological, and not appropriate in a scientific account.A teleological account can be circular (tautological) if the end result of some process is explained as due to that process having a purpose. [Consider the usefulness as an 'explanation' that 'oganisms tend to become more complex over time as nature strives for complexity'. 2]
Scientists today are expected to offer accounts which do not presuppose endpoints. That does not mean that a scientists cannot believe there is purpose in the world, or even that the universe was created by a purposeful God – simply that scientific accounts cannot 'cheat' by using arguments that something happens because God wished it, or nature was working towards it. That is, it should not make any difference whether a scientist believes God is the ultimate cause of some phenomena (through creating the world, and setting up the laws of nature) as science is concerned with the natural 'mechanisms' and causes of events.
In the part of his treatise on bodies that concerns living things, Digby gives an account of two 'engines' he had seen many years before when he was travelling in Spain. This was prior to the invention of the modern steam engine, and these engines were driven by water (as in water mills). 3
Digby introduces two machines which he considers illustrate "the natures of these two kinds of bodies [i.e., plants and animals]"
He gives a detailed account of one of the engines, explaining that the mechanism has one basic function – to supply water to an elevated place above a river.
1/4
2/4
3/4
4/4
His other engine example (apparently recalled in less detail – he acknowledges having a "confused and cloudy remembrance" ) was installed in a mint in a mine where it had a number of different functions, including:
producing metal of the correct thickness for coinage
stamping the metal with the coinage markings
cutting the coins from the metal
transferring the completed coins into the supply room.
These days we might see it as a kind of conveyor belt moving materials through several specialist processes.
Different classes of engine
Digby seems to think this is a superior sort of engine to the single function example.
For Digby, the first type of engine is like a plant,
"Thus then; all sorts of plants, both great and small, may be compared to our first engine of the waterwork at Toledo, for in them all the motion we can discern, is of one part transmitting unto the next to it, the juice which it received from that immediately before it…"
Digby comparing a plant to a single function machine
The comments here about juice may seem a bit obscure, as Digby has an extended explanation (over several pages) of how the growth and structure of a plant are based on a single kind of vascular tissue and a one-way transport of liquid. 4 Liquid rises up through the plant just as it was raised up by the mechanism at Toldeo
The multi-function 'engine' (perhaps ironically better considered in today's terms as an industrial plant!) is however more like an animal,
"But sensible living creatures, we may fitly compare to the second machine of the mint at Segovia. For in them, though every part and member be as it were a complete thing of itself, yet every one requires to be directed and put on in its motion by another; and they must all of them (though of very different natures and kinds of motion) conspire together to effect any thing that may be for the use and service of the whole. And thus we find in them perfectly the nature of a mover and a moveable; each of them moving differently from one another, and framing to themselves their own motions, in such sort as is more agreeable to their nature, when that part which sets them on work hath stirred them up.
And now because these parts (the movers and the moved) are parts of one whole; we call the entire thing automaton or…a living creature".
Digby comparing animals to more complex machines (language slightly tidied for a modern reader)
So plants were to animals as a single purpose mechanism was to a complex production line.
Animals as super-plants
Digby thought animals and plants shared in key characteristics of generation (we would say reproduction), nutrition, and augmentation (i.e., growth), as well as suffering sickness, decay and death. But Digby did not just think animals were different to plants, but a superior kind.
He explains this both in terms of the animal having functions that be did not beleive applied to plants,
And thus you see this plant [sic] has the virtue both of sense or feeling; that is, of being moved and affected by external objects lightly striking upon it; as also of moving itself, to or from such an object; according as nature shall have ordained.
but he also related to this as animals being more complex. Whereas the plant was based on a vascular system involving only one fluid, this super-plant-like-entity, had three. In summary,
this plant [sic, the animal] is a sensitive creature, composed of three sources, the heart, the brain, and the liver: whose are the arteries, the nerves, and the veins; which are filled with vital spirits, with animal spirits, and with blood: and by these the animal is heated, nourished, and made partaker of sense and motion.
A historical analogy to explain the superiority of animals to plants
[The account here does not seem entirely consistent with other parts of the book, especially if the reader is supposed to associate a different fluid with each of the three systems. Later in the treatise, Digby refers to Harvey's work about circulation of the blood (including to the liver), leaving the heart through arteries, and to veins returning blood to the heart. His discussion of sensory nerves suggest they contain 'vital spirits'.]
Some comments on Digby's analogy
Although some of this detail seems bizarre by today's standards, Digby was discussing ideas about the body that were fairly widely accepted. As suggested above, we should not criticise those living in previous times for not sharing current understandings (just as we have to hope that future generations are kind to our reasonable mistakes). There are, however, two features of this use of analogy I thought worth commenting on from a modern point of view.
The logic of making the unfamiliar familiar
If such analogies are to be used in teaching and science communication, then they are a tactic we can use to 'make the unfamiliar familiar', that is to help others understand what are sometimes difficult (e.g., abstract, counter-intuitive) ideas by pointing out they are somewhat like something the person is already familiar with and feels comfortable that they understand.
In a teaching context, or when a scientist is being interviewed by a journalist, it is usually important that the analogue is chosen so it is already familiar to the audience. Otherwise either the analogy does not help explain anything, or time has to be spent first explaining the analogy, before it can be employed.
In that sense, then, we might question Digby's example as not being ideal. He has to exemplify the two types of machines he is setting up as the analogue before he can make an analogy with it. Yet this is not a major problem here for two reasons.
Firstly, a book affords a generosity to an author that may not be available to a teacher or a scientist talking to a journalist or public audience. Reading a book (unlike a magazine, say) is a commitment to engagement in depth and over time, and a reader who is still with Digby by his Chapter 23 has probably decided that continued engagement is worth the effort.
Secondly, although most of his readers will not be familiar with the specific 'engines' he discusses from his Spanish travels, they will likely be familiar enough with water mills and other machines and devices to readily appreciate the distinction he makes through those examples. The abstract distinction between two classes of 'engine' is therefore clear enough, and can then be used as an analogy for the difference between plants and animals.
A biased account
However, today we would not consider this analogy to be applicable, even in general terms, leaving aside the now discredited details of plant and animal anatomy and physiology. An assumption behind the comparison is that animals are superior to plants.
In part, this is explained in terms of the plants apparent lack of sensitivity (later 'irritability' would be added as a characteristic of living things, shared by plants) and their their lack of ability in getting around, and so not being able to cross the room to pick up some object. In part, this may be seen as an anthropocentric notion: as humans who move around and can handle objects, it clearly seems to us with our embodied experience of being in the world that a form of life that does not do this (n.b., does not NEED to do this) is inferior. This is a bit like the argument that bacteria are primitive forms of life as they have evolved so little (a simplification, of course) over billions of years: which can alternatively be understood as showing how remarkably adapted they already were, to be able to successfully occupy so many niches on earth without changing their basic form.
There is also a level of ignorance about plants. Digby saw the plant as having a mechanism that moved moisture from the soil through the plant, but had no awareness of the phloem (only named in the nineteenth century) that means that transport in a plant is not all in one direction. He also did not seem to appreciate the complexity of seasonal changes in plants which are much more complex than a mechanism carrying out a linear function (like lifting water to a privileged person who lives above a river). He saw much of the variation in plant structures as passive responses to external agents. His idea of human physiology are also flawed by today's standards, of course.
Moreover, in Digby's scheme (from simple minerals dug from the ground, to accidentally compacted complex materials, to plants and then animals) there is a clear sense of that long-standing notion of hierarchy within nature.
The great chain of being
That is, the great chain of being, which is a system for setting out the world as a kind of ladder of superior and inferior forms. Ontology is sometimes described as the study of being , and typologies of different classes of entities are sometimes referred to as ontologies. The great chain of being can be understood as a kind of ontology distinguishing the different types of things that exist – and ranking them.
In this scheme (or rather schemes, as various versions with different levels of detail and specificity had been produced – for example discriminating the different classes of angels) minerals come below plants, which come below animals. To some extent Digby's analogy may reflect his own observations of animals and plants leading him to think animals were collectively and necessarily more complex than plants. However, ideas about the great chain of being were part of common metaphysical assumptions about the world. That is, most people took it for granted that there was such hierarchy in nature, and therefore they were likely to interpret what they observed in those terms.
Digby made the comparison between increasing complexity in moving from plant to animal as being a similar kind of step-up as when moving from inorganic material to plants,
But a sensitive creature, being compared to a plant, [is] as a plant is to a mixed [inorganic] body; you cannot but conceive that he must be compounded as it were of many plants, in like sort as a plant is of many mixed bodies.
Digby, then, was surely building his scheme upon his prior metaphysical commitments. Or, as we might say these days, his observations of the world were 'theory-laden'. So, Digby was not only offering an analogy to help discriminate between animals and plants, but was discriminating against plants in assuming they were inherently inferior to animals. I think that is a bias that is still common today.
Work cited:
Digby, K. (1644/1665). Two Treatises: In the one of which, the nature of bodies; In the other, the nature of mans soule, is looked into: in ways of the discovery of the immortality of reasonable soules. (P. S. MacDonald Ed.). London: John Williams.
Digby, K. (1644/2013). Two Treatises: Of Bodies and of Man's Soul (P. S. MacDonald Ed.): The Gresham Press.
1 This is a fascinating book with many interesting examples of analogies, similes, metaphor, personification and the like, and an interesting early attempt to unify forces (here, gravity and magnetism). (I expect to write more about this over time.) The version I am reading is a 2013 edition (Digby, 1644/2013) which has been edited to offer consistent spellings (as that was not something many authors or publishers concerned themselves with at the time). The illustrations, however, are from a facsimile of an original publication (Digby, 1644/1645: which is now out of copyright so can be freely reproduced).
2 Such explanations may be considered as a class of 'pseudo-explanations': that give the semblance of explanation without actually explaining very much (Taber & Watts, 2000).
3 The aeolipile (e.g., Hero's engine) was a kind of steam engine – but was little more than a novelty where water boiled in a vessel with suitably directed outlets and free to rotate, causing it to spin. However, the only 'useful' work done was in turning the engine itself.
4 This relates to his broader theory of matter which still invokes the medieval notion of the four elements, but is also an atomic theory involving tiny particles that can pass into apparently solid materials due to pores and channels much too small to be visible.
It seems atoms are not quite as chemists imagine them not to be
Keith S. Taber
A research paper presenting a new model of atomic and molecular structure was recently brought to my attention. 1
The paper header
'New Atomic Model with Identical Electrons Position in the Orbital's and Modification of Chemical Bonds and MOT [molecular orbital theory]' 2 is published in a recently-launched journal with the impressive title of Annals of Atoms and Molecules. This is an open-access journal available free on the web – so readily accessible to chemistry experts, as well as students studying the subject and lay-people looking to learn from a scholarly source. [Spoiler alert – it may not be an ideal source for scholarly information!]
In the paper, Dr Morshed proposes a new model of the atom that he suggests overcomes many problems with the model currently used in chemistry.
A new model of atomic structure envisages East and West poles as well as North and South poles) (Morshed, 2020a, p.8)
Of course, as I have often pointed out on this blog, one of the downsides of the explosion in on-line publishing and the move to open access models of publication, is that anyone can set up as an academic journal publisher and it can be hard for the non-expert to know what reflects genuine academic quality when what gets published in many new journals often seems to depend primarily upon an author being willing to pay the publisher a hefty fee (Taber, 2013).
That is not to suggest open-access publishing has to compromise quality: the well-established, recognised-as-prestigious journals can afford to charge many hundreds of pounds for open-access publication and still be selective. But, new journals, often unable to persuade experienced experts to act as reviewers, will not attract many quality papers, and so cannot be very selective if they are to cover costs (or indeed make the hoped-for profits for their publishers).
A peer reviewed journal
The journal with the impressive title of Annals of Atom and Molecules has a website which explains that
"Annals of Atoms and Molecules is an open access, peer reviewed journal that publishes novel research insights covering but not limited to constituents of atoms, isotopes of an element, models of atoms and molecules, excitations and de-excitations, ionizations, radiation laws, temperatures and characteristic wavelengths of atoms and molecules. All the published manuscripts are subjected to standardized peer review processing".
So, in principle at least, the journal has experts in the field critique submissions, and advise the editors on (i) whether a manuscript has potential to be of sufficient interest and quality to be worth publishing, and (ii) if so, what changes might be needed before publications is wise.
Standardisedpeer review gives the impression of some kind of moderation (perhaps renormalisation given the focus of the journal? 3) of review reports, which would involve a lot of extra work and another layer of administration in the review process…but I somehow suspect this claim really just meant a 'standard' process. This does not seem to be a journal where great care is taken over the language used.
Effective peer review relies on suitable experts taking on the reviewing, and editors prepared to act on their recommendations. The website lists five members of the editorial board, most of whom seem to be associated with science departments in academic institutions:
Prof. Farid Menaa (Fluorotronics Inc) 4
Prof. Sabrin Ragab Mohamed Ibrahim (Department of Pharmacognosy and Pharmaceutical chemistry, Taibah University)
Prof. Mina Yoon (Department of Physics and Astronomy, University of Tennessee)
Dr. Christian G Parigger (Department of Physics, University of Tennessee Space Institute)
Dr. Essam Hammam El-Behaedi (Department of Chemistry and Biochemistry, University of North Carolina Wilmington)
The members of a journal Editorial Board will not necessarily undertake the reviewing themselves, but are the people entrusted by the publisher with scholarly oversight of the quality of the journal. For this journal it is claimed that "Initially the editorial board member handles the manuscript and may assign or the editorial staff may assign the reviewers for the received manuscript". This sounds promising, as at least (it is claimed) all submissions are initially seen by a Board member, whether or not they actually select the expert reviewers. (The 'or' means that the claim is, of course, logically true even if in actuality all of the reviewers are assigned by the unidentified office staff.)
At the time of writing only three papers have been published in the Annals. One reviews a spectroscopic method, one is a short essay on quantum ideas in chemistry – and then there is Dr Morshed's new atomic theory.
A new theory of atomic structure
The abstract of Dr Morshed's paper immediately suggests that this is a manuscript which was either not carefully prepared or has been mistreated in production. The first sentence is:
The concept of atom has undergone numerous changes in the history of chemistry, most notably the realization that atoms are divisible and have internal structure Scientists have known about atoms long before they could produce images of them with powerful magnifying tools because atoms could not be seen, the early ideas about atoms were mostly founded in philosophical and religion-based reasoning.
Morshed, 2020a, p.6
Presumably, this was intended to be more than one sentence. If the author made errors in the text, they should have been queried by the copy editor. If the production department introduced errors, then they should have been corrected by the author when sent the proofs for checking. Of course, a few errors can sometimes still slip through, but this paper has many of them. Precise language is important in a research paper, and sloppy errors do not give the reader confidence in the work being reported.
The novelty of the work is also set out in the abstract:
In my new atomic model, I have presented the definite position of electron/electron pairs in the different orbital (energy shells) with the identical distance among all nearby electron pairs and the degree position of electrons/electron pairs with the Center Point of Atoms (nucleus) in atomic structure, also in the molecular orbital.
Morshed, 2020a, p.6
This suggests more serious issues with the submission than simple typographical errors.
Orbital /energy shells
The term "orbital (energy shells)" is an obvious red flag to any chemist asked to evaluate this paper. There are serious philosophical arguments about precisely what a model is and the extent to which a model of the atom might be considered to be realistic. Arguably, models that are not mathematical and which rely on visualising the atom are inherently not realistic as atoms are not the kinds of things one could see. So, terms such as shell or orbital are either being used to refer to some feature in a mathematical description or are to some extent metaphorical. BUT, when the term shell is used, it conventionally means something different from an orbital.
That is, in the chemical community, the electron shell (sic, not energy shell) and the orbital refer to different classes of entity (even if in the case of the K shell there is only one associated orbital). Energy levels are related, but again somewhat distinct – an energy level is ontologically quite different to an orbital or a shell in a similar way to how sea level is very different in kind to a harbour or a lagoon; or how 'mains voltage' is quite different from the house's distribution box or mains ring; or how an IQ measurement is a different kind of thing to the brain of the person being assessed.
Definite positions of electrons
An orbital is often understood as a description of the distribution of the electron density – we might picture (bearing in mind my point that the most authentic models are mathematical) the electron smeared out as in a kind of time-lapse representation of where the electron moves around the volume of space designated as an orbital. Although, as an entity small enough for quantum effects to be significant (a 'quanticle'? – with some wave-like characteristics, rather than a particle that is just like a bearing ball only much smaller), it may be better not to think of the electron actually being at any specific point in space, but rather having different probabilities of being located at specific points if we could detect precisely where it was at any moment.
That is, if one wants to consider the electron as being at specific points in space then this can only be done probabilistically. The notion of "the definite position of electron/electron pairs in the different orbital" is simply nonsensical when the orbital is understood in terms of a wave function. Any expert asked to review this manuscript would surely have been troubled by this description.
It is often said that electrons are sometimes particles and sometimes waves but that is a very anthropocentric view deriving from how at the scale humans experience the world, these seem very distinct types of things. Perhaps it is better to think that electrons are neither particles nor waves as we experience them, but something else (quanticles) with more subtle behavioural repertoires. We think that there is a fundamental inherent fuzziness to matter at the scale where we describe atoms and molecules.
So, Dr Morshed wants to define 'definite positions' for electrons in his model, but electrons in atoms do not have a fixed position. (Later there is reference to circulation – so perhaps these are considered as definite relative positions?) In any case, due to the inherent fuzziness in matter, if an electron's position was known absolutely then there would would (by the Heisenberg uncertainty principle) be an infinite uncertainty in its momentum, so although we might know 'exactly' where it was 'now' (or rather 'just now' when the measurement occurred as it would take time for the signal to be processed through first our laboratory, and then our nervous, apparatus!) this would come with having little idea where it was a moment later. Over any duration of time, the electron in an atom does not have a definite position – so there is little value in any model that seeks to represent such a fixed position.
The problem addressed
Dr Morshed begins by giving some general historical introduction to ideas about the atom, before going on to set out what is argued to be the limitation of current theory:
Electrons are arranged in different orbital[s] by different numbers in pairs/unpaired around the nuclei. Electrons pairs are associated by opposite spin together to restrict opposite movement for stability in orbital rather angular movements. The structural description is obeyed for the last more than hundred years but the exact positions of electrons/pairs in the energy shells of atomic orbital are not described with the exact locations among different orbital/shells.
Morshed, 2020a, p.6
Some of this is incoherent. It may well be that English is not Dr Morshed's native language, in which case it is understandable that producing clear English prose may be challenging. What is less forgivable is that whichever of Profs. Ibrahim, Yoon, or Drs Menaa, Parigger, or El-Behaedi initially handled the manuscript did not point out that it needed to be corrected and in clear English before it could be considered for publication, which could have helped the author avoid the ignominy of having his work published with so many errors.
That assumes, of course, that whichever of Ibrahim, Yoon, Menaa, Parigger, or El-Behaedi initially handled the manuscript were so ignorant of chemistry to be excused for not spotting that a paper addressing the issue of how current atomic models fail to assign "exact positions of electrons/pairs in the energy shells of atomic orbital are not described with the exact locations among different orbital/shells" both confused distinct basic atomic concepts and seemed to be criticising a model of atomic structure that students move beyond before completing upper secondary chemistry. In other words, this paper should have been rejected on editorial screening, and never should have been sent to review, as its basic premise was inconsistent with modern chemical theory.
If, as claimed, all papers are seen by the one of the editorial board, then the person assigned as handling editor for this one does not seem to have taken the job seriously. (And as only three papers have been published since the journal started, the workload shared among five board members does not seem especially onerous.)
Just in case the handling editorial board member was not reading the text closely enough, Dr Morshed offered some images of the atomic model which is being critiqued as inadequate in the paper:
A model of the atom criticised in the paper in Annals of Atoms and Molecules (Morshed, 2020a, p.7)
Again, the handling editor should have noticed that these images in the figure reflect the basic model of the atom taught in introductory school classes as commonly represented in simple two-dimensional images. These are not the models used to progress knowledge in academic chemistry today.
These images are not being reproduced in the research paper as part of some discussion of atomic representations in school textbooks. Rather this is the model that the author is suggesting falls short as part of current chemical theory – but it is actually an introductory pedagogical model that is not the basis of any contemporary chemical research, and indeed has not been so for the best part of a century. Even though the expression "the electrons/electron pairs position is not identical by their position, alignments or distribution" does not have any clear meaning in normal English, what is clear is that these very simple models are only used today for introductory pedagogic purposes.
Symmetrical atoms?
The criticism of the model continues:
The existing electrons pair coupling model is not also shown clearly in figure by which a clear structure of opposite spine pair can be drowned. Also there are no proper distribution of electron/s around the center (nuclei) to maintain equal number of electrons/electronic charge (charge proportionality) around the total mass area of atomic circle (360°) in the existing atomic model (Figure 1). There are no clear ideas about the speed proportion and time of circulation of electrons/electron pairs in the atomic orbital/shells so there is no answer about the possibility of uneven number of electrons/electron pairs at any position /side of atomic body can arise that must make any atom unstable.
Morshed, 2020a, p.7
Again, this makes little sense (to me at least – perhaps the Editorial Board members are better at hermeneutics than I am). Now we are told that electrons are 'circulating' in the orbitals/shell which seems inconsistent with them having the "definite positions" that Dr Morshed's model supposedly offers. Although I can have a guess at some of the intended meaning, I really would love to know what is meant by "a clear structure of opposite spine pair can be drowned".
Protecting an atom from drowning? (Images by Image by ZedH and Clker-Free-Vector-Images from Pixabay)
A flat model of the atom
I initially thought that Dr Morshed is concerned that the model shown in figure 1 cannot effectively show how in the three dimensional atomic structure the electrons must be arranged to give a totally symmetric patterns: and (in his argument) that this would be needed else it would leave the atoms unstable. Of course, two dimensional images do not easily show three dimensional structure. So when Dr Morshed referred to the "atomic circle (360°) in the existing atomic model" I assumed he was actually referring to the sphere.
On reflection, I am not so sure. I was unimpressed by the introduction of cardinal points for the atom (see Dr Morshed's figure 2 above, and figure 4 below). I could understand the idea of a nominal North and South pole in relation to the angular momentum of the nucleus and electrons 'spinning up or down' – but surely the East and West poles are completely arbitrary for an atom as any point on the 'equator' could be used as the basis for assigning these poles. However, if Dr Morshed is actually thinking in terms of a circular (i.e., flat) model of the atom, and not circular representations of a spherical model of atomic structure then atoms would indeed have an Occident and an Orient! The East pole WOULD be to the right when the atom has the North pole at the top as is conventional in most maps today. 5
But atoms are not all symmetrical?
But surely most atoms are not fully symmetrical, and indeed this is linked to why most elements do not commonly exist as discrete atoms. The elements of those that do, the noble gas elements, are renown for not readily reacting because they (atypically for atoms) have a symmetrical electronic 'shield' for the nuclear charge. However, even some of these elements can be made cold enough to solidify – as the van der Waals forces allow transient fluctuating dipoles. So the argument seems to be based on a serious alternative conception of the usual models of atomic structure.
It is the lack of full symmetry in an atom of say, fluorine, or chlorine, which means that although it is a neutral species it has an electron affinity (that is, energy is released when the anion is formed) as an electron can be attracted to the core charge where it is not fully shielded.
The reference to "time of circulation of electrons/electron pairs in the atomic orbital/shells" seems to refer to a mechanical model of orbital motion, which again, has no part in current chemical theory.
Preventing negative electron pairs repelling each other
Dr Morshed suggests that the existing model of atomic structure cannot explain
Why the similar charged electrons don't feel repulsion among themselves within the same nearby atomic orbital of same atom or even in the molecular orbital when two or more atomic orbital come closer to form molecular orbital within tinier space though there is more possibility of repulsion between similar charged electrons according to existing atomic model.
Morshed, 2020a, p.7
Electrons do not feel repulsion for the same reason they do not feel shame or hunger or boredom – or disdain for poor quality journals. Electrons are not the kind of objects that can feel anything. However, this anthropomorphic expression is clearly being used metaphorically.
I think Dr Morshed is suggesting that the conventional models of atomic structure do not explain why electrons/electron pairs do not repel each other. Of course, they do repel each other – so there is no need to look for an explanation. This then seems to be an alternative conception of current models of the atom. (The electrons do not get ejected from the atom as they are also attracted to the nucleus – but, if they did not repel each other, there would be no equilibrium of forces, and the structure of the atom would not be stable.)
A new model of atomic structure supposedly reflects the 'proper' angles between electrons in atoms (Morshed, 2020, p.9)
Dr Morshed suggests that his model (see his Figure 4) 'proves the impossibility of repulsion between any electron pairs' – even those with similar charges. All electron pairs have negative (so similar) charges – it is part of the accepted definition of an electron that is is a negatively charged entity. I do not think Dr Morshed is actually suggesting otherwise, even if he thinks the electrons in different atoms have different magnitudes of negative charge (Morshad, 2020b).
Dr Morshed introduces a new concept that he calls 'center of electron pairs neutralization point'.
This is the pin-point situated in a middle position between two electrons of opposite spin pairs. The point is exactly between of opposite spine electron pairs so how the opposite electronic spin is neutralized to remaining a stable electron pair consisting of two opposite spin electrons. This CENP points are assumed to be situated between the cross section of opposite spine electronic pair's magnetic momentum field diameter (Figure 3).
Morshed, 2020a, p.8
The yellow dot represents a point able to neutralise the opposite spin of a pair of electrons(!), and is located at the point found by drawing a cross from the ends of the ⥯ symbols used to show the electron spin! This seems to be envisaged a real point that has real effects, despite being located in terms of the geometry of a totally arbitrary symbol.
So, the electron pair is shown as a closely bound pair of electrons with the midspot of the complex highlighted (yellow in the figure) as the 'center of electron pairs neutralization point'. Although the angular momentum of the electrons with opposite spin leads to a magnetic interaction between them, they are still giving rise to an electric field which permeates through the space around them. Dr Morshed seems to be suggesting that in his model there is no repulsion between the electron pairs. He argues that:
According to magnetic attraction/repulsion characteristics any similar charges repulse or opposite charges attract when the charges energy line is in straight points. If similar charged or opposite charged end are even close but their center of energy points is not in straight line, there will be no attraction or repulsion between the charges (positive/negative). Similarly, when electrons are arranged in energy shells around the nucleus the electrons remain in pairs within opposite spin electrons where the poses a point which represent as the center of repulsion/attraction points (CENP) and two CENP never come to a straight within the atomic orbital so the similar charged electrons pairs don't feel repulsion within the energy shells.
Morshed, 2020a, pp.8-9
A literal reading of this makes little sense as any two charges will always have their centres in a straight line (from the definition of a straight line!) regardless of whether similar or opposite charges or whether close or far apart.
My best interpretation of this (and I am happy to hear a better one) is that because the atom is flat, and because the electron pairs have spin up and spin down electrons, with are represented by a kind of ⥮ symbol, the electrons in some way shield the 'CENP' so that the electron pair can only interact with another charge that has a direct line of sight to the CENP.
Morshed seems to be suggesting that although electron pairs are aligned to allow attractions with the nucleus (e.g., blue arrows) any repulsion between electron pairs is blocked because an electron in the pair shields the central point of the pair (e.g., red arrow and lines)
There are some obvious problems here from a canonical perspective, even leaving aside the flat model of the atom. One issue is that although electrons are sometimes represented as ↿ or ⇂ to indicate spin, electrons are not actually physically shaped like ↿. Secondly, pairing allows electrons to occupy the same orbital (that is, have the same set of principal, azimuthal and magnetic quantum numbers) – but this does not mean they are meant to be fixed into a closely bound entity. Also, this model works by taking the idea of spin direction literally, when – if we do that – electrons can have only have spin of ±1/2. In a literal representation such as used by Dr Morshed he would need to have ALL his electrons orientated vertically (or at least all at the same angle from the vertical). So, the model does not work in its own terms as it would prevent most of the electron pairs being attracted to the nucleus.
Morshed's figure 4 'corrected' given that electrons can only exist in two spin states. In the (corrected version of the representation of the) Morshed model most electron pairs would not be attracted to the nucleus.
A new (mis)conception of ionic bonding
Dr Morshed argues that
In case of ionic compound formation problem with the existing atomic model is where the transferred electron will take position in the new location on transferred atom? If the electrons position is not proportionally distributed along total 360 circulating area of atom, then the position of new transferred electron will cause the polarity in every ion (both cation and anion forms by every transformation of electrons) so the desired ionization is not possible thus every atom (ion) would become dipolar. On the point of view any ionization would not possible i.e., no ionic bonded compound would have formed.
Morshed, 2020, p.7
Again, although the argument may have been very clear to the author, this seems incoherent to a reader. I think Dr Morshed may be arguing that unless atoms have totally symmetrical electrons distributions ("proportionally distributed along total 360 circulating area of atom") then when the ion is formed it will have a polarity. Yet, this seems entirely back to front.
If the atom to be ionised was totally symmetric (as Dr Morshed thinks it should be), then forming an ion from the atom would require disrupting the symmetry. Whereas, by contrast, in the current canonical model, we assume most atoms are not symmetrical, and the formation of simple ions leads to a symmetric distribution of electrons (but unlike in the noble gas atoms, a symmetrical electron distribution which does not balance the nuclear charge).
Dr Morshad illustrates his idea:
Ionic bond formation represented by an non-viable interaction between atoms (Morshed, 2020, p.10)
Now these images show interactions between discrete atoms (a chemically quite unlikely scenario, as discrete atoms of sodium and chlorine are not readily found) that are energetically non-viable. As has often been pointed out, the energy released when the chloride ion is formed is much less than the energy required to ionise the sodium atom, so although this scheme is very common on the web and in poor quality textbooks, it is a kind of chemical fairy tale that does not relate to any likely chemical context. (See, for example, Salt is like two atoms joined together.)
The only obvious difference between these two versions of the fairly tale (if we ignore that in the new version both protons and neutrons appear to be indicated by + signs which is unhelpful) seems to be that the transferred electron changes its spin for some reason that does not seem to be explained in the accompanying text. The explanation that is given is
My new atomic model with identical electrons pair angle position is able to give logical solution to the problems of ion/ionic bond formation. As follows: The metallic atom which donate electrons during ion formation from outermost orbital, the electrons are arranged maintaining definite degree angle around 360° atomic mass body shown in (Figure 4). After the transformation the transferred electron take position at the vacant place of the transferred atoms outermost orbital, then instant the near most electrons/pairs rearrange their position in the orbital changing their angle position with the CPA [central point of the atom, i.e., the nucleus] due to electromagnetic repulsion feeling among the similar charged electrons/pairs. Thus the ionic atom gets equal electron charge density around whole of their 360° atomic mass body resulting the cation and anion due to the positive and negative charge difference in atomic orbital with their respective nucleus. Thus every ion becomes non polar ion to form ionic bond within two opposite charged ion (Figure 5).
Morshed, 2020, p.9
So, I think, supposedly part (b) of Dr Morshed's figure 5 is meant to show, better than part (a), how the electron distribution is modified when the ion is formed. It would of course be quite possible to show this in the kind of representations used in (a), but in any case it does not look any more obvious in (b) to my eye!
So, figure 5 does not seem to show very well Dr Morshed's solution to a problem I do not think actually exists in the context on a non-viable chemical process. Hm.
Finding space for the forces
Another problem with the conventional models, according to Dr Morshed, is that, as suggested in his figures 6 and 7 is that the current models do not leave space for the 'intermolecular' [sic, intramolecular] force of attraction in covalent bonds.
In current models, according to Morshed's paper, electrons get in the way of the covalent bond (Morshed, 2020, p.11)
Dr Morshad writes that
According to present structural presentation of shared paired electrons remain at the juncture of the bonded atomic orbital, if they remain like such position they will restrict the Inter [sic] Molecular Force (IMF) between the bonded atomic nuclei because the shared paired electron restricts the attraction force lying at the straight attraction line of the bonded nuclei the shown in (Figure 6a).
Morshed, 2020, p.11
There seem to be several alternative conceptions operating here – reflecting some of the kind of confusions reported in the literature from studies on students' ideas.
Just because the images are static two dimensional representations, this does not mean electrons are envisaged to be stationary at some point on a shell;
and just because we draw representations of atoms on flat paper, this does not mean atoms are flat;
The figure is meant to represent the bond, which is an overall configuration of the nuclei and the electrons, so there is not a distinct intramolecular force operating separately;
Without the electrons there would be no "Inter [sic] Molecular Force (IMF) between the bonded atomic nuclei" as the nuclei repel each other: the bonding electrons do not restrict the intramolecular force (blocking it, because they lie between the nuclei), but are crucial to it existing.
Regarding the first point here, Dr Morshed suggests
Covalent bonds are formed by sharing of electrons between the bonded atoms and the shared paired electrons are formed by contribution of one electron each of the participating atoms. The shared paired electrons remain at the overlapping chamber (at the juncture of the overlapped atomic orbital).
Morshed, 2020, p.9
That is, according to Dr Morshed's account of current atomic theory, in drawing overlapping electron shells, the electrons of the bond which are 'shared' (and that is just a metaphor, of course) are limited to the area shown as overlapping. This is treating an abstract and simplistic representation as if it is realistic. There is no chamber. Indeed, the molecular orbital formed by the overlap of the atomic orbitals will 'allow' the electrons to be likely to be found within quite a (relatively – on an atomic scale) large volume of space around the bond axis. Atomic orbitals that overlap to form molecular orbitals are in effect replaced by those molecular orbitals – the new orbital geometry reflects the new wavefunction that takes into account both electrons in the orbital.
So, if there has been overlap, the contributing atomic orbitals should be considered to have been replaced (not simply formed a chamber where the circles overlap), except of course Dr Morshed 's figures 6 and 7 show shells and do not actually represent the system of atomic orbitals.
Double bonds
This same failure to interpret the intentions and limitation of the simplistic form of representation used in introductory school chemistry leads to similar issues when Dr Morshed considers double bonding.
A new model of atomic structure suggests an odd geometry for pi bonds (Morshed, 2020, p.12)
Dr Morshed objects to the kind of representation on the left in his figure 8 as two electron pairs occupy the same area of overlap ('chamber'),
Yet, in the model Dr Morshed employs he had claimed that electron pairs do not repel unless they are aligned to allow a direct line of sight between their CNPs. In any case, the figure he criticises does not show overlapping orbitals, but overlapping L shells. He suggests that the existing models (which of course are not models currently used in chemistry except in introductory classes) imply the double bond in oxygen must be two sigma bonds: "The present structure of O2 molecule show only two pairs of electron with head to head overlapping in the overlapping chamber i.e., two sigma bond together which is impossible" (p.12).
However, this is because a shell type presentation is being used which is suitable for considering whether a bond is single or double (or triple), but no more. In order to discuss sigma and pi bonds with their geometrical and symmetry characteristics, one must work with orbitals, not shells. 6
Yet Dr Morshed has conflated shells and orbitals throughout his paper. His figure 8a that supposedly shows "Present molecular orbital structural showing two shared paired electrons in the same overlapped chamber" does not represent (atomic, let alone molecular) orbitals, and is not intended to suggest that the space between overlapping circles is some kind of chamber.
"The remaining two opposite spin unpaired electrons in the two bonded [sic?] Oxygen's outer- most orbital [sic, shell?] getting little distorted towards the shared paired electrons in their respective atomic orbital then they feel an attraction among the opposite spin electrons thus they make a bond pairs by side to side overlapping forms the pi-bond"
Morshed, 2020, p.12.
It is not at all clear to see how this overlap occurs in this representation (i.e., 8b). Moreover, the unpaired electrons will not "feel an attraction" as they are both negatively charged even if they have anti-parallel spins. The scheme also makes it very difficult to see how the pi bond could have the right symmetry around the bond axis, if the 'new molecular orbital structure' was taken at face value.
Conclusion
Dr Morshed's paper is clearly well meant, but it does not offer any useful new ideas to progress chemistry. It is highly flawed. There is no shame in producing highly flawed manuscripts – no one is perfect, which is why we have peer review to support authors in pointing out weaknesses and mistakes in their work and so allowing them to develop their ideas till they are suitable for publication. Dr Morshed has been badly let down by the publishers and editors of Annals of Atoms and Molecules. I wonder how much he was charged for this lack of service? 7
Publishing a journal paper like this, which is clearly not ready to make a contribution to the scholarly community through publication, does not only do a disservice to the author (who will have this publication in the public domain for anyone to evaluate) but can potentially confuse or mislead students who come across the journal. Confusing shells with orbitals, misrepresenting how ionic bonds form, implying that covalent bonds are due to a force between nuclei, suggesting that electron pairs need not repel each other, suggesting a flat model of the atom with four poles… there are many points in this paper that can initiate or reinforce student misconceptions.
Supposedly, this manuscript was handled by a member of the editorial board, sent to peer reviewers and the publication decision based on those review reports. It is hard to imagine any peer reviewer who is actually an academic chemist (let alone an expert in the topics published in this journal) considering this paper would be publishable, even with extensive major revisions. The whole premise of the paper (that simple representations of atoms with concentric shells of electrons reflect the models of atomic and molecular structure used today in chemistry research) is fundamentally flawed. So:
were there actually any reviews? (Really?)
if so, were the reviews carried out by experts in the field? (Or even graduate chemists or physicists?)
were the reviews positive enough to justify publication?
If the journal feels I am being unfair, then I am happy to publish any response submitted as a comment below.
Dr Menaa, Prof. Ibrahim, Prof. Yoon, Dr Parigger, Dr El-Behaedi…
If you were the Board Member who handled this submission and you feel my criticisms are unfair, please feel free to submit a comment. I am happy to publish your response.
Or, if you were not the Board Member who (allegedly) handled this submission, and would like to make that clear…
Works cited:
Gilbert, W. (1600/2016). On the Magnet, Magnetic Bodies, and the Great Magnet of the Earth. A new science, with many both arguments and experiment proofs. (V. Wilmont, Trans.): Lulu.com.
Morshed, A. M. A. (2020a). New Atomic Model with Identical Electrons Position in the Orbital's and Modification of Chemical Bonds and MOT. Annals of Atoms and Molecules, 2(1), 6-13.
1 I thank Professor Eric Scerri of UCLA for bringing my attention to the deliciously named 'Annals of Atoms and Molecules', and this specific contribution.
2 That is my reading of the abbreviation, although the author uses the term a number of times before rather imprecisely defining it: "Similar solution can be made for molecular orbital (MOT) as such as: The molecular orbital (MO) theory…" (p.10).
3 Renormalisation is the name given to a set of mathematical techniques used in areas such as quantum field theory when calculations give implausible infinite results in order to 'lose' the unwanted infinities. Whilst this might seem like cheating – it is tolerated as it works very well.
4 I was intrigued that 'Prof.' Farid Menaa seemed to work for a non-academic institution, as generally companies cannot award the title of Professor. Of course, Prof. Meena may also have an appointment at a university that partners the company, or could have emeritus status having retired from academia.
I found him profiled on another publisher's site as "Professor, Principal Investigator, Director, Consultant Editor, Reviewer, Event Organizer and Entrepreneur,…" who had worked in oncology, dermatology, haemotology (when "he pioneered new genetic variants of stroke in sickle cell anemia patients" which presumably is much more positive than it reads). Reading on, I found he had 'followed' complementary formations in "Medecine [sic], Pharmacy, Biology, Biochemistry, Food Sciences and Technology, Marine Biology, Chemistry, Physics, Nano-Biotechnology, Bio-Computation, and Bio-Statistics" and was "involved in various R&D projects in multiple areas of medicine, pharmacy, biology, genetics, genomics, chemistry, biophysics, food science, and technology". All of which seemed very impressive (nearly as wide a range of expertise as predatory journal publishers claim for me), but made me none the wiser about the source of his Professorial title.
5 Today. Although interestingly, in the first major comprehensive account of magnetism, Gilbert (1600/2016) tended to draw the North-South axis of the earth horizontally in his figures.
6 The representations we draw are simple depictions of something more subtle. If the circles did represent orbitals then they could not show the entire volume of space where the electron might be found (as this is theoretically infinite) but rather an envelope enclosing a volume where there is the highest probability (or 'electron density'). So orbitals will actually overlap to some extent even when simple images suggest otherwise.
Anthropomorphic language refers to non-human entities as if they have human experiences, perceptions, and motivations. Both non-living things and non-human organisms may be subjects of anthropomorphism. Anthropomorphism may be used deliberately as a kind of metaphorical language that will help the audience appreciate what is being described because of its similarly to some familiar human experience. In science teaching, and in public communication of science, anthropomorphic language may often be used in this way, giving technical accounts the flavour of a persuasive narrative that people will readily engage with. Anthropomorphism may therefore be useful in 'making the unfamiliar familiar', but sometimes the metaphorical nature of the language may not be recognised, and the listener/reader may think that the anthropomorphic description is meant to be taken at face value. This 'strong anthropomorphism' may be a source of alternative conceptions ('misconceptions') of science.
The first example was from the lead story about 'long COVID'.
Prof. Onur Boyman, Director of the Department of Immunology at the University Hospital, Zurich, was interviewed after his group published a paper suggesting that blood tests may help identify people especially susceptible to developing post-acute coronavirus disease 2019 (COVID-19) syndrome (PACS) – which has become colloquially known as 'long COVID'.
"We found distinct patterns of total immunoglobulin (Ig) levels in patients with COVID-19 and integrated these in a clinical prediction score, which allowed early identification of both outpatients and hospitalized individuals with COVID-19 that were at high risk for PACS ['long COVID']."
Cervia, Zurbuchen, Taeschler, et al., 2022, p.2
The study reported average patterns of immunoglobulins found in those diagnosed with COVID-19 (due to SARS-CoV-2 infection), and those later diagnosed with PACS. The levels of different types of immunoglobulins (designated as IgM, etc.) were measured,
Differentiating mild versus severe COVID-19, IgM was lower in severe compared to mild COVID-19 patients and healthy controls, both at primary infection and 6-month follow-up… IgG3 was higher in both mild and severe COVID-19 cases, compared to healthy controls …In individuals developing PACS, we detected decreased IgM, both at primary infection and 6-month follow-up… IgG3 tended to be lower in patients with PACS…which was contrary to the increased IgG3 concentrations in both mild and severe COVID-19 cases…
Cervia, Zurbuchen, Taeschler, et al., 2022, p.3
Viruses in a defensive mode
In the interview, Professor Boyman discussed how features of the immune system, and in particular immunoglobulins, were involved in responses to infection, and made the comment:
"IgG3…is smaller than IgM and therefore it is able to go into many more tissues. It is able to cross certain tissue barriers and go into those sites where viruses might actually try to go to and hide"
Prof. Onur Boyman interviewed on 'BBC Inside Science'
This is anthropomorphic as it refers to viruses trying to hide from the immune components. Of course, viruses are not sentient, so they do not try to do anything: they have no intentions. Although viruses might well pass across tissue barriers and move into tissues where they are less likely to come into contact with immunoglobulins, 'hiding' suggests a deliberate behaviour – which is not the case.
Professor Boyman is clearly aware of that, and either deliberately or otherwise was speaking metaphorically. Scientifically literate people would not be misled by this as they would know viruses are not conscious agents. However, learners are not always clear about this.
The bacteria, however, are going on the offensive
The other point I spotted was later in the same programme when the presenter, Gaia Vince, introduced an item about antibiotic resistance:
"Back in my grandparent's time, the world was a much more dangerous place with killer microbes lurking everywhere. People regularly died from toothache, in childbirth, or just a simple scratch that got infected. But at the end of the second world war, doctors had a new miracle [sic] drug called penicillin. Antibiotics have proved a game changer, taking the deadly fear away from common infections. But the microbes did not just accept defeat, they have been mounting their resistance and they are making a comeback."
Gaia Vince presenting 'Inside Science'
Antibiotics are generally ineffective against viruses, but have proved very effective treatments for many bacterial infections, including those that can be fatal when untreated. The functioning of antibiotics can be explained by science in purely natural terms, so the label of 'miracle drugs' is a rhetorical flourish: their effect must have seemed like a miracle when they first came into use, so this can also be seen as metaphoric language.
Bacteria regrouping for a renewed offensive? (Image by WikiImages from Pixabay )
However, again the framing is anthropomorphic. The suggestion that microbes could 'accept defeat' implies they are the kind of entities able to reflect on and come to terms with a situation – which of course they are not. The phrase 'mounting resistance' also has overtones of deliberate action – but again is clearly meant metaphorically.
Again, there is nothing wrong with these kinds of poetic flourishes in presenting science. Most listeners would have heard "microbes did not just accept defeat, they have been mounting their resistance and they are making a comeback" and would have spontaneously understood the metaphoric use of language without suspecting any intention to suggest microbes actually behave deliberately. Such language supports the non-specialist listener in accessing a technical science story.
Some younger listeners, however, may not have a well-established framework for thinking about the nature of an organism that is able to reflect on its situation and actively plan deliberate behaviours. After all, a good deal of children's literature relies on accepting that various organisms, indeed non-living entities such as trains, do have human feelings, motives and behavioural repertoires. (Learners may for example think that evolutionary adaptations, such as having more fur in a cold climate, are mediated by conscious deliberation.) Popular science media does a good job of engaging and enthusing a broad audience in science, but with the caveat that accessible accounts may be open to misinterpretation.
Work cited:
Cervia, C., Zurbuchen, Y., Taeschler, P. et al.(2022) Immunoglobulin signature predicts risk of post-acute COVID-19 syndrome. Nature Communications, 13, 446. https://doi.org/10.1038/s41467-021-27797-1
Because it has different levels of structure providing functionality
Keith S. Taber
I have been working on a book about pedagogy, and was writing something about sequencing teaching. I was setting out how well-planned teaching has a structure that has several levels of complexity – and I thought a useful analogy here (as the book is primarily aimed at chemistry educators) might be protein structure.
Proteins are usually considered to have at least three, or often four, levels of structure. Protein structure is not just of intellectual interest, but has critical functional importance. It is the shape, conformation, of the protein molecule which allows it to have its function. Now, I should be careful here, as I am well aware (and have discussed on the site) how the language we often use when discussing organisms can seem teleological.
We analyse biological structures and processes, and when considering the component parts can see them as having some function in relation to that overall structure or process. That can give the impression of purpose – as though someone designed the shape of the protein with a particular function in mind. That can give the impression of teleological thinking – seeing nature as having a purpose. The scientific understanding is that proteins with their complex shapes that are just right for their observed functions have been subject to natural selection over a very long period – evolving along with the structures and processes they are part of.
The importance of protein shape
The shape of a protein can allow it to act as a catalyst that will allow, say, a polysaccharide to break down into simple sugars at body temperature and at a rate that can support an organism's metabolism (when the rate without the enzyme would only give negligible amounts of product ). The shape of a protein, as in haemoglobin, may allow a complex to exist which either binds with oxygen or releases it depending on the local conditions in different parts of the body. And so forth.
Now, chemically, proteins are of the form of polyamides – substances that can be understood to have a molecular structure of connected amide units (above left, source: Wikipedia) in a long chain that results from polymerising amino acid units (amino acid structure shown above right, source: Wikipedia). An amino acid molecule has two functional groups – an amide group (-NH2) which allows the compounds to react with carboxylic acids (including amino acids for example), and a carboxylic acid group (-COOH) that allows the compound to react with amides (including amino acids for example). So, amino acids can polymerise as each amino acid molecule has two sites that can be loci for the reaction.
Molecular structure of a compound formed by four amino acids – the peptide linkage (highlighted orange) is formed from part (-CO-) of the acid group (-COOH, as outlined in red) of one amino acid molecule with part (-NH-) of the amine group (-NH2, as outlined in cyan) of another amino acid molecule (which may be of the same or a different amino acid). In proteins the chains are much longer. Original image from Wikipedia
Special examples of polyamides
So, proteins are polyamides. But this does not mean that polyamides are proteins. In the same way that chemistry Nobel prize winners are scientists – but not all scientists are Nobel laureates. So, being a polyamide is a necessary, but not a sufficient, condition for being a protein. For examples, nylons are also polyamides, but are not proteins. 1
Proteins tend to be very complex polyamides, which are built up from a number of different amino acids (of which 20 are found in proteins). Each amino acid has a different molecular structure – there is the common feature which allows the peptide linkages to form, but each amino acid also has a different side chain or 'residue' as part of its molecule. But just being a large, complex, polypeptide built from a selection of those 20 amino acids does not necessarily lead to a protein found in livings things. The key point about the protein is that its very specific shape allows it to have the function it does. Indeed there are many billions of polyamide structures of similar complexity to naturally found proteins which could exist (and perhaps do somewhere), but which have no role in living organisms (on this planet at least!)
A simple teaching analogy often used to explain enzyme specificity is that of a lock and key. Whilst somewhat simplistic, if we consider that the protein has to have just the right shape to 'fit' the 'substrate' molecule then it is clear that the precise shape is important. A key that opens a door lock has to be precisely shaped. (The situation with an enzyme is actually more demanding, as the molecule can change its shape according to whether a substrate is bound – so it needs to be the right shape to bind to the substrate molecular and then the right shape to release the product molecule.)
So a functioning protein molecule has a very specific shape, indeed sometimes a specific profile of shapes as it interacts with other molecules, and this can be understood to arise from several levels of structure.
Four levels of structure
The primary structure is the sequence of amino acid residues along the polypeptide skeleton.
The amino acid sequence in polypeptide chains in human insulin (with the amino acids represented by conventional three letter abbreviations) – image from Saylor Academy, 2012 open access text: The Basics of General, Organic, and Biological Chemistry
The chain is not simply linear, or a zigzag shape (as we might commonly represent an organic molecules based on a chain of carbon atoms). Rather the interactions between the peptide units, causes the chain to form a more complex three-dimensional structure, such as a helix. This is the secondary structure.
Protein chains tend to form into shapes such as helices (This example: Crystal structure of the DNA-binding protein Sso10a from Sulfolobus solfataricus; from the protein data base PDB DOI: 10.2210/pdb4AYA/pdb.)
Because the secondary structure allows the amino acid residues on different parts of the chain to be close, interactions, forms of bonding, form between different points on the chain. (As shown in the representation of the insulin structure above.) This depends on the amino acid sequence as the different residues have different sizes, shapes and functional groups – so interactions will occur between particular residue pairs. This adds another level of structure.
A coiled cable can take on various overall shapes (Image by Brett Hondow from Pixabay )
Imagine taking a coiled cable somewhat like the helical secondary structure), such as used for some headphone, and folding this into a more complex shape. This is the tertiary structure, and gives the protein its unique shape, which it turn makes it suitable to act as an enzyme or hormone or whatever.
Proteins may be even more complex, as they may comprise complexes of several chains, closely bound together by weak chemical bonds. Haemoglobin, for example, has four such subunits arranged in a quaternary structure.
A representation of the structure of a haemoglobin protein – with the four interlinked chains shown in different colours (Structure determination of haemoglobin from Donkey (equus asinus) at 3.0 Angstrom resolution, from the protein data base: PDB DOI: 10.2210/pdb1S0H/pdb)
But what has this got to do with sequencing curriculum?
When planning teaching, such as when developing a course or writing a 'scheme of work', one has to consider how to sequence the introduction of course material as well as learning activities. This can be understood to have different levels in terms of the considerations we might take into account.
A well-designed curriculum sequence has several levels of structure (ordering, building, cross-linking) affording more effective teaching
Primary structure and conceptual analysis
A fundamental question (once we have decided what falls within the scope of the course, and selected the subject matter) is how to order the introduction of topics and concepts. There is usually some flexibility here, but as some concepts are best understood in terms of other more fundamental ideas, there are more and less logical ways to go about this. 'Conceptual analysis' is the technique which is used to break down the conceptual structure of material to see what prerequisite learning is necessary before discussing new material.
For example, if we wish to teach for understanding then it probably does not make sense to introduce double bonds before the concept of covalent bonds, or neutralisation before teaching something about acids, or d-level splitting before introducing ideas about atomic orbitals, or the rate determining step of a reaction before teaching about reaction rate. In biology, it would not make sense to teach about mitochondria before the concept of cells had been introduced. In physics, one would not seek to teach about conservation of momentum, before having introduced the concept of momentum. The reader can probably think of many more examples. The sequence of quanta of subject matter in the curriculum sequence can be considered a first level of curriculum structure.
Secondary structure and the spiral curriculum
We also revise topics periodically at different levels of treatment. We introduce topics at an introductory level – and later offer more sophisticated accounts (atomic structure, acidity, oxidation…). We distinguish metals form non-metals and later introduce electronegativity. We distinguish ionic and covalent bonds and later introduce degrees of bond polarity. In recent years this has been reflected in the work on developing model 'learning progressions' that support students in more sophisticated scientific thinking over several grade levels.
This builds upon the well-established idea of a 'spiral curriculum' (Bruner, 1960) where the learner resists topics in increasing levels of sophistication over their student career. So, here is a level of structure beyond the linear progression of topics covered in different sessions, encompassing revisiting the same topic at different turns of the 'spiral' (perhaps like the alpha helices formed in may proteins).
This already suggests there will be linkages across the 'chain' of teachings units (whether seen as lectures/lesson or lesson episodes) as references are made back to earlier teaching in order to draw upon more fundamental ideas in building up more complex ideas, and building on simplified accounts to develop more nuanced and sophisticated accounts.
Tertiary structure – drip feeding to reinforce learning
The skilled teacher will also be making other links that are not strictly* essential but are useful unless the students have exemplary study skills usually ARE essential!]
To support students in consolidating learning (something that is usually essential if we want them to remember the material and be able to apply it months later) the teacher will 'drip feed' reinforcement of prior learning by looking for opportunities to revise key points form earlier teaching.
We have defined what we mean by 'compound' or 'oxidising agent' or 'polymer', so now we spot opportunities to reinforce this whenever it seems sensible to do so in teaching other material. We have taught students to calculate molecular mass, or assign oxidation states, or recognise a Lewis acid – so we look for opportunities to ask students to rehearse and apply this knowledge in contexts that arise in later teaching. At the end of a previous lesson everyone seemed to understand the difference between respiration and breathing – but it sensible to find opportunity for them to rehearse the distinction. 2
There is then a level of structure due to linkages back and forth between the components of the teaching sequence.
So where the 'primary structure' is necessary to build up knowledge in a logical way in order that the teaching scheme functions to provide a coherent learning experience (teaching makes sense at the time), and the secondary structure allows progression toward more sophisticated accounts and models as students develop, the 'tertiary structure' offers reinforcement of learning to ensure the course functions as an effective long term learning experience (that what was taught is not just understood at the time, but is retained, and readily brought to mind in relevant contexts, and can be applied, over the longer term).
Quaternary structure – locating the course in the wider curriculum experience
What about quaternary structure? Well, commonly a student is not just attending one class or lecture course. Their curriculum consists of several different strands of teaching experiences. At upper secondary school level, for example, the learner may attend chemistry classes interspersed with physics classes, biology classes and mathematics classes. Their experience of the curriculum encompasses these different strands. Likely, there are both salient and other less obvious potential linkages between these different courses. Conservation of energy from physics applies in chemistry and biology. Enzymes are catalysts, so the characteristics of catalysts apply to them. The nature of hydrogen bonds may be taught in chemistry – and applied in biology. In that case, it would be useful for the learners if the topic was taught that concept in the chemistry class before it was needed in biology.
And just as there may be aspects of logical sequencing of ideas across the strands to be considered, there may be other potential links where the teacher in one subject can draw upon, exemplify, or provide opportunities to review, what has been taught in the other.
Level of structure
Feature of sequencing
primary structure
logical sequencing of concepts to identify and later build on prerequisites
secondary structure
spiral curriculum to build up sophistication of understanding
tertiary structure
cross-linking between lessons along strand to reinforce learning by finding opportunities to revisit, review, and apply prior learning
quaternary structure
cross links between courses to build up integrated (inter-*)disciplinary knowledge
levels of structure in well-designed curriculum
(* in a degree course this may be coordinating different lecture courses within a discipline; in a school context this may be relating different curriculum subjects)
Afterword
How seriously do I intend this comparison? Of course this is just an analogy. It is easy to see that it does not hold up to detailed analysis – there are more ways that curricular structure is quite unlike protein structure, and the kinds of units and links being discussed in the two cases are of very different nature.
Is there any value in such a comparison if the analogy is somewhat shallow? Well, devices such as analogies operate as thinking tools. Most commonly we use teaching analogies to help 'make the unfamiliar familiar' by showing how something unfamiliar is somewhat like something familiar. This can be a useful first stage in helping someone understand some new phenomena or concept.
In teaching science we commonly make analogies with everyday phenomena to help introduce abstract science concepts. Here I am using a scientific concept (protein structure) as the analogue for the target idea about sequencing teaching.
My motivation here was to prompt teachers (and others who might read the book when it is finished) who are already familiar with general ideas about curriculum and schemes of work to think about a parallel (albeit, perhaps a somewhat forced one?) with something rather different but likely already very familiar – protein structure. Chemists and science teachers are likely to already appreciate the different levels of structure in proteins, and how the different aspects of the nature of polypeptide chains and the links formed between amino acid residues inform the overall shape, and therefore the functionality, of the structure.
Perhaps this thinking tool will entice readers to think about how conceptual links within and between courses of study can support the functionality of teaching? Perhaps they will dismiss the comparison, pointing out various ways in which the level of structure in a well-planned curriculum are quite different from the levels of structure in a protein. Of course, if they can do that insightfully, I might suspect that this 'teaching analogy' will have done its job.
Work cited:
Bruner, J. S. (1960). The Process of Education. New York: Vintage Books.
This posting has nothing to do with the chemical composition of your brain (where lipids do play an important part), nor about diet – such as those claims of the merits of 'omega-3 fatty acids' in a healthy diet.
Rather, I am going to suggest how a chemical structure can provide an analogy for thinking about working memory.
In a sense, working memory is a bit like triglyceride structure (which is only a useful comparison for those who already know about the chemistry being referenced)
Analogies are used in teaching and in science communication to help 'make the unfamiliar familiar', to show someone that something they do not (yet) know about is actually, in some sense at least, a bit like something they are already familiar with. In an analogy, there is a mapping between some aspect(s) of the structure of the target ideas and the structure of the familiar phenomenon or idea being offered as an analogue. Such teaching analogies can be useful to the extent that someone is indeed highly familiar with the 'analogue' (and more so than with the target knowledge being communicated); that there is a helpful mapping across between the analogue and the target; and that comparison is clearly explained (making clear which features of the analogue are relevant, and how).
So, the similarly is in terms of conceptual structures. Consider the figure above, which suggests there are similarities between aspects of the concept of working memory and aspects of the concept of triglyceride structure. In this case the analogy is at quite an abstract level – so is only likely to be useful for more advanced learners (such as science graduates preparing for teaching for example).
In relation to science, we might distinguish between several classes of analogy. In teaching we are most likely to be explaining some target scientific idea in terms of an everyday idea or phenomenon. However, sometimes one scientific idea which is already well-established is used as the analogue by which to explain about a less familiar scientific idea. This can happen in science teaching or science communication to the public – but can also be employed by scientists themselves when communication new ideas to their peers. It is also possible that sometimes a scientific idea may be useful as an analogue for explaining some target idea from outside science (as long, of course, as the science is familiar to the audience for the analogy).
My professional life has basically encompassed teaching about three broad areas – teaching natural science (mainly chemistry and physics) to school and college learners; teaching educational ideas to those preparing for school teaching; and teaching about research to those setting out on research projects.
The analogy I am discussing here came to me when preparing the manuscript for a book aimed at teachers of chemistry (an audience of readers that I can reasonably assume have a high level of chemistry knowledge) and broadly about pedagogy. So, what came to mind was an analogy from science to put across an idea about what is known as working memory.
Working memory
Working memory is the name given to the faculty or apparatus we all have to support conscious thinking – when we plan, assess and evaluate, problem solve, and so forth. It is absolutely critical to our nature as deliberate thinkers. We probably do MUCH more thinking (if you allow that term in this context, if not, say, cognitive processing) pre-consciously, so without any awareness. This is the 'thinking' [or cognitive processing] that goes on in the background, much of which is quite low level, but also includes the kind of incubation of problems that leads to those sudden insights where a solution comes to us (i.e., to our conscious awareness) in a 'flash'. It is also the basis of those intuitions that we describe as 'gut feelings' and which are often powerful (and often turn out to be correct) even though we are not sure what we are basing them on.
Yet working memory is where we do the thinking that we are aware of, and supports the stream of consciousness that is the basis of our awareness of ourselves as thinking beings. Given its importance, a very interesting finding is that although the brain potentially has a virtually inexhaustible capacity for learning new information (through so called 'long-term memory'), the working memory itself where we process material we are trying to learn and memorise has a very limited capacity. Indeed, it is often said that typical working memory capacity in a normal adult is 7±2. And some think that may be an overestimate. So, a typical person can juggle no more than about seven items in mind at once.
There is a very important question of why such an important aspect of cognition is so limited. Is there some physical factor which has limited this, or some evolution contingency that is in effect an unlucky break in human evolution? There is also the intriguing suggestion that actually this very limited capacity may have survival value and so be considered an adaptation increasing fitness.1 Whatever the reason – we have a working memory that can be considered to only have about half a dozen slots for information. (Of course, 'slots' is here a metaphor, but a useful one.)
Chunking
Each slot will take one item of information, except that we have to be careful what we mean by one 'item', as the brain acts to treat such 'items' subjectively. That is, what counts as one item for your brain may not work as one item for mine. Consider the following example:
1s22s22p63s1
How many 'items' is that string of symbols? If we consider someone who only saw this as a series of numbers and letters and who had never come across this before they would need to remember:
the number 1,
is followed by the lower-case letter s,
followed by the number 2,
which is a superscript,
then the number 2,
then the lower-case letter s,
then the number 2,
which is a superscript,
…
and quite likely we have exceeded memory capacity when only half way through!
But for a chemist who already knows that this particular string could be seen as the electronic structure of a sodium atom,2 this can be treated as one unit – the whole string is already available represented as an integrated structurein long-term memory form where it can be copied as 'a chunk' into working memory to occupy a single slot. So, a chemistry teacher using this information in an argument or calculation has other 'slots' for the other relevant information whereas a student may be struggling.
Triglycerides as an analogue for working memory
It struck me that an analogy that would be familiar to many chemists and science teachers is that of triglycerides which are considered esters of glycerol (with its three alcohol groups) with fatty acids. Although this class of compounds has some commonalities, there are a great many possible different specific structures (each strictly reflecting a distinct compound). What is common is the short chain of three carbons each bonded to an ester linkage (left hand figure below). However, what those ester linkages actually link to can vary. In human milk, for example, there are a great many different triglycerides (at least of the order of hundreds) comprising a wide range of fatty acids (Winter, Hoving & Muskiet, 1993).3
The triglycerides are members of a class of compounds with common features. They can be considered to be the result of glycerol (propane-1,2,3-triol) reacting with fatty acids, where the compounds formed will depend upon the specific fatty acids. The first figure uses R as a generic symbol to show the common structure. The second figure is the simplest triglyceride type structure formed when the acid is methanoic acid. If a mixture of acids is reacted with the glycerol, the side chains need not be the same – as in the third example. Actual triglycerides found in fats and oils in organisms usually have much longer chains than in this example.
In the image above, meant to be a simple representation of the structure of triglyceride molecules, the first figure has Rs to represent any of a great many possible side chains. The shortest possible structure here just has hydrogen atoms for Rs (triformin – the second figure), but more commonly there are long aliphatic chains as suggested by the third figure – although usually the chains would be even longer. In relation to diet, a key feature of interest is whether the fats consumed are saturated, or have some degree of 'unsaturation' (i.e., the double bond shown in the middle chain of the third figure) – unsaturated fats tend to be seen as more healthy, and tend to come from plant sources.
We might consider that the molecular structures consists of the common component with three 'slots' for side chains. In principle the slots could be occupied by hydrogens (hydrogen 'atoms') or chains based on any number of carbons (carbon 'atoms').4 So the total mass of a triglyceride molecule can vary considerably, as can the number of carbon centres in a molecule.
Fixed 'slots', variable content
Working memory is sometimes said to have 'slots' as well (again, to be understood metaphorically) into which information from perception or memory can be 'slotted'. We can consciously operate on the information in working memory, for example forming associations between the material in different slots. The number of slots in a person's working memory is fixed, but as information that has been well learnt can be 'chunked' into quite extensive conceptual structures, the total amount of information that can be engaged with is highly variable.
Working memory has a very limited number of 'slots' – but where extensive conceptual frameworks are already well established from prior learning a great deal of information can be engaged with as a single chunk
If student in class is keeping in mind information that is not directly related to the task in hand then this will 'use up' slots that are not then available for problem-solving or other tasks. Indeed, one of the skills someone with expert knowledge in a field has, but not novices, is determining which information available is likely to be peripheral or incidental rather that important to the task in hand, and indeed which of the important features need to be considered initially, and which can be ignored until later.
The perceived complexity of a learning task then always has to be considered in relation to the background knowledge and experience of the individual. So, at one time a person may be watching a documentary on a subject they know nothing about, in which case the information they perceive may seen unconnected, such that working memory may be occupied by very small chunks (such as individual names of unfamiliar people that are bring discussed). If that same person sits down to revise course notes they have developed over an extended time time, and have reviewed regularly, they may be bringing to mind quite extensive conceptual structures to slot into working memory. The same working memory, with the same nominal capacity, is now engaging with a much more extensive body of information.
Work cited:
Winter, C. H., Hoving, E. B., & Muskiet, F. A. J. (1993). Fatty acid composition of human milk triglyceride species: Possible consequences for optimal structures of infant formula triglycerides. Journal of Chromatography B: Biomedical Sciences and Applications, 616(1), 9-24. doi:https://doi.org/10.1016/0378-4347(93)80466-H
Footnotes
1 The logic here is that, because of chunking, working memory biases cognition towards what is already familiar, which may be an advantage in a context where although change is important there is a largely stable environment so that developing and then following a stable set of survival strategies is generally advantageous.
The kind of fruit that was edible yesterday is probably edible today, and the animal that attacked the group last week is best assumed to be dangerous today as well. The peer who helped us yesterday may help us again in future if we reciprocate, and the person who tried to cheat us before is best not trusted too far today.
2 There is a strong case that the familiar designation of electronic structures in terms of discrete s, p, d and f orbitals is only strictly valid for hydrogenic (single electron) species – but the model is commonly taught and used in chemical explanations relating to multi-electron atoms.
3 Strictly there are no fatty acids 'in' the triglycerol just as strictly there are no atoms in a molecule.4 I am here using economy of language which will be clear to the expert, though we risk misleading novice students if we are not careful to be precise. The triglycerides have various chain segments corresponding to a wide range of fatty acids; a wide range of fatty acids are generated by hydrolysing the triglyceride.
4 Strictly 'atomic centres', as molecules do not contain atoms, as atoms are by definition discrete structures with only one nucleus – and the atomic centres in molecules are bound into a molecular structure. Again, chemists and teachers may refer to carbon atoms in the side chain knowing this is not precisely what they mean, but we should perhaps be careful to be clear when talking to learners.
Do I have any old spectrometers lying around that I no longer need?
Keith S. Taber
"Any old iron, any old iron Any, any, any old iron An old iron pot, an old iron cot An old iron bicycle or anything you've got An old iron plate, an old iron grate yer mother used to fry on And I'm going to let my country have me old watch-chain! Old iron, old iron!"
From 'Any old iron' – a music hall song written by Harry Champion in 1911. 'Any old iron' was (is?) a traditional call used by scrap merchants collecting unwanted items that could be melted down for recycling
An email offers to help me 'get rid of' obsolete lab equipment:An email asking if I have any old lab apparatus to dispose of. The opening claim is false – none of my research works mention this brand of lab. instruments. Clearly, if Andreas had read my research, he would not be contacting me in this way. (Why is it so acceptable nowadays to simply lie when approaching people?)
Dear Andreas
Thank you for your message, enquiring about instrumentation you suggest I referred to in my recent published work. It is pleasing to think you are looking at my work. However, I am not sure which study you are referring to:
Whichever article it was, I do hope you found it of interest.
Best wishes
Keith
I have written about analytical instruments used in the laboratory – but analysis in my educational research did not use them (figure from Taber, 2012)
Being flummoxed by a student question was the inspiration for a teaching metaphor
Keith S. Taber
An artist's impression of the author being lost for words (Image actually by Christian Dorn from Pixabay)
In my teaching on the 'Educational Research' course I used to present a diagram of a shape something like the lemniscate – the infinity symbol, ∞ – and tell students that was the shape their research project and thesis should take. I would suggest this was a kind of visual metaphor.
This may seem a rather odd idea, but I was actually responding to a question I had previously been asked by a student. Albeit, this was a rather deferred response.
'Lost for words'
As a teacher one gets asked all kinds of questions. I've often suggested that preparing for teaching is more difficult than preparing for an examination. When taking an examination it is usually reasonable to assume that the examination question have been set by experts in the subject.
A candidate therefore has a reasonable chance of foreseeing at least the general form of the questions that night asked. There is usually a syllabus or specification which gives a good indication of the subject matter and the kinds of skills expected to be demonstrated – and usually there are past papers (or, if not, specimen papers) giving examples of what might be asked. The documentation reflects some authority's decisions about the bounds of the subject being examined (e.g., what counts as included in 'chemistry' or whatever), the selection of topics to be included in the course, and the level of treatment excepted at this level of study (Taber, 2019). Examiners may try to find novel applications and examples and contexts – but good preparation should avoid the candidate ever being completely stumped and having no basis to try to develop a response.
However, teachers are being 'examined' so to speak, by people who by definition are not experts and so may be approaching a subject or topic from a wide range of different perspectives. In science teaching, one of the key issues is how students do not simply come to class ignorant about topics to be studied, but often bring a wide range of existing ideas and intuitions ('alternative conceptions') that may match, oppose, or simply be totally unconnected with, the canonical accounts.
This can happen in any subject area. But a well prepared teacher, even if never able to have ready answers to all question or suggestions learners might offer, will seldom be lost for words and have no idea how to answer. But I do recall an occasion when I was indeed flummoxed.
I was in what is known as the 'Street' in the main Faculty of Education Building (the Donald McIntyre Building) at Cambridge at a time when students were milling about as classes were just ending and starting. Suddenly out of the crowd a student I recognised from teaching the Educational Research course loomed at me and indicated he wanted to talk. I saw he was clutching a hardbound A4 notebook.
We moved out of the melee to an area where we could talk. He told me he had a pressing question about the dissertation he had to write for his M.Phil. programme.
"What should the thesis look like?"
His question sounded simple enough – "What should the thesis look like?"
Now at one level I had an answer – it should be an A4 document that would be eventually bound in blue cloth with gold lettering on the spine. However, I was pretty sure that was not what he meant.
What does a thesis look like?
I said I was not sure what he meant. He opened his notebook at a fresh double page and started sketching, as he asked me: 'Should the thesis look like this?' as he drew a grid on one page of his book. Whilst I was still trying to make good sense of this option, he started sketching on the facing page. "Or, should it look like this?"
I have often thought back to this exchange as I was really unsure how to respond. He seemed no more able to explain these suggestions than I was able to appreciate how these representations related to my understanding of the thesis. As I looked at the first option I was starting to think in terms of the cells as perhaps being the successive chapters – but the alternative option seemed to undermine this. For, surely, if the question was about whether to have 6 or 8 chapters – a question that has no sensible answer in abstract without considering the specific project – it would have been simpler just to pose the question verbally. Were the two columns (if that is what they were) meant to be significant? Were the figures somehow challenging the usual linear nature of a thesis?
I could certainly offer advice on structuring a thesis, but as a teacher – at least as the kind of constructivist teacher I aspired to be – I failed here. I was able to approach the topic from my own perspective, but not to appreciate the student's own existing conceptual framework and work from there. This if of course what research suggests teachers usually need to do to help learners with alternative conceptions shift their thinking.
Afterwards I would remember this incident (in a way I cannot recall the responses I gave to student questions on hundreds of other occasions) and reflect on it – without ever appreciating what the student was thinking. I know the student had a background in a range of artistic fields including as a composer – and I wondered if this was informing his thinking. Perhaps if I had studied music at a higher level I might have appreciated the question as being along the lines of, say, whether the should the thesis be, metaphorically speaking, in sonata form or better seen as a suite?
I think it was because the question played on my mind that later, indeed several years later, I had the insight that 'the thesis' (a 'typical' thesis) did not look like either of those rectangular shapes, but rather more like the leminscape:
A visual metaphor for a thesis project (after Taber, 2013)
The focus of a thesis
My choice of the leminscate was because its figure-of-eight nature made it two loops which are connected by a point – which can be seen as some kind of focal point of the image:
A thesis project has a kind of focal point
This 'focus' represents the research question or questions (RQ). The RQ are not the starting point of most projects, as good RQ have to be carefully chosen and refined, and that usually take a lot of reading around a topic.
However, they act as a kind of fulcrum around which the thesis is organised because the sections of the thesis leading up to the RQ are building up to them – offering a case for why those particular questions are interesting, important, and so-phrased. And everything beyond that point reflects the RQ, as the thesis then describes how evidence was collected and analysed in order to try to answer the questions.
Two cycles of activity
A thesis project cycles through expansive and focusing phases
Moreover, the research project described in a thesis reflects two cycles of activity.
The first cycle has an expansive phase where the researcher is reading around the topic, and exposing themselves to a wide range of literature and perspectives that might be relevant. Then, once a conceptual framework is developed from this reading (in the literature review), the researcher focuses in, perhaps selecting one of several relevant theoretical perspectives, and informed by prior research and scholarship, crystallises the purpose of the project in the RQ.
Then the research is planned in order to seek to answer the RQ, which involves selecting or developing instruments, going out and collecting data – often quite a substantive amount of data. After this expansive phase, there is another focusing stage. The collected data is then processed into evidence – interpreted, sifted, selected, summarised, coded and tallied, categorised – and so forth – in analysis. The data analysis is summarised in the results, allow conclusions to be formed: conclusions which reflect back to the RQ.
The lemniscate, then, acts a simple visual metaphor that I think acts as a useful device for symbolising some important features of a research project, and so, in one sense at least, what a thesis 'looks' like. If any of my students (or readers) have found this metaphor useful then they have benefited from a rare occasion when a student question left me lost for words.
Should a University be an academic community – or a business?
Keith S. Taber
surely we want students from underrepresented groups emailing their friends back at school or college using their University of Cambridge email addresses
Does giving someone an email address make a University responsible for their correspondence? (Image by Muhammad Ribkhan from Pixabay)
The University of Cambridge is currently undertaking an internal consultation about a plan to change its email policy relating to emails with the @cam.ac.uk address – a change that would remove such email accounts from many who currently have them.
This has come shortly after the University has moved its email from its own servers and outsourced them to the cloud – or, more precisely, Microsoft's cloud. And that came fairly soon after the University decided (rather abruptly, and without proper notice, in my own view – but that's all current under the bridge) to withdraw the opportunity for each member to have personal webpages on the University servers. However, the potential change in policy is not supposed to be about saving costs, but rather a principled change concerned with the University considering its email domain as part of its corporate identity, where it may be considered to have responsibilities (that raise security considerations) in a similar way to how it has responsibilities on its physical sites.
The logic seems to be that just as the University has responsibility over information published on any webpages appearing in its domain (e.g., they should not misrepresent; they should not be used to advance scams; they should not be discriminatory or defamatory, etc.) it also has responsibility for communications sent from @cam.ac.uk addresses.
There seem to be two related aspects of what is considered to follow from this:
cam.ac.uk email addresses should only be used by those who have a current active role in the University
cam.ac.uk email addresses should primarily be used for University business
I must confess when I first read the proposed policy (which I am not copying verbatim as it is currently not in the public domain, but is accessible to current students and staff) I could see the reasonableness of it. Certainly, when one remembers the political capital that was made out of Hilary Clinton failing to carefully separate her 'work' from 'personal' email activity, and the possibility that that may have been a major factor in the election of Donald Trump as U.S. President, nominal leader of the free world, and commander-in-chief of the largest nuclear armed force of any democratic nation, it gives pause for thought.
Yet, the more I have thought about this, the more this seems a very questionable direction of travel. The reason this has raised a lot of concern in the wider Cambridge University community (including those people who see themselves as still members of that community – often after many years of service – despite no longer being in formal roles) is because many retired staff who have Cambridge emails will lose their accounts. This includes a good many who may never have had another email address – and until now did not think they needed multiple accounts. However, I think the bigger issue is the separation of University related communication (you should use cam.ac.uk) from unrelated communication (you should not). First, however, let's consider the potentially ex-communicated.
To be ex-communicated from the Cambridge domain
To many people who have multiple email accounts, or have moved accounts from time to time, it may seem that the soon-to-be-disqualified account holders, usually former employees of the university or its colleges, are either making a fuss without cause, or at least worrying unduly. It is not difficult to obtain a new email account, and re-direction tools are available that will make sure any email sent to the old account will be forwarded for some time (the University has promised this if the new policy is implemented). Of course, it is a hassle to have to change addresses and let people know – but, even so, many estate agents manage to stay in business.
The real issue here is more a matter of identity. People who identify as part of the wider University community are being told they no longer quality to be 'in' the system. Now, the University has a separate email system for its former alumni (@cantab.net) which is being offered to (at least most of) those being disqualified – so, that might seem to solve this problem. After all, we are only talking about an email address and @cantab.net can be understood as an indicator of being not currently active in the University, but still part of the wider community.
Distributed responsibility for denying email accounts
However, some of those threatened with this relegation in their email status may question this: anyone who is a graduate of the University (for example) can have an @cantab.net address even if they have not been in Cambridge, or had any involvement in any activities here, for years – or even decades. Some of those retired staff who still use their @cam.ac.uk addresses consider they are still actively involved in the life of the University. The new policy suggests that in such cases the head of institution (a head of Department/Faculty or House {College}) can sponsor former staff to retain their email address for a limited period if they have a specific role. So, as a hypothetical example, a retired member of staff invited back to sit on some working party because of their special expertise could qualify whilst that group was in operation.
But what counts as sufficient engagement is left to the appropriate head of institution. If they make a positive judgement, they then need to request the email account being kept active, and the decision has to be revisited periodically. Many retired colleagues who are former employees, fellows, or members, of my own College, Homerton, are members of the Homerton Retired Senior Member's Association. This group has a committee, and volunteers undertaking leadership of various activities, and many members engage (well, as COVID allows) in college activities.
Would this be counted?
…only for Committee Members?
Or does this kind of engagement not count at all?
Presumably it will be for the Principal of the College to decide – and for the heads of other houses to decide (perhaps using quite different criteria) on parallel cases in their own colleges.
Can you be a University Officer if you are not considered actively engaged in the University?
By my reading of the new policy, some University Officers will not automatically retain @cam.ac.uk domain email addresses. That certainly seems to be the case for Emeritus Officers like myself. The University grants the title of Emeritus Professor or Emeritus Reader to its more senior teaching officers on retirement. So, people granted such titles are no longer on the payroll – as they are no longer employed by the University – but are formally recognised as, technically at least, Officers of the University.
I assume this is so (assume? As an Emeritus Officer I've never been given any formal briefing on the status) in part to recognise service, but in part because at least some of these Emeritus Officers are undertaking activities that the University will consider it benefits from being associated with.
Although I am retired, I then still have a formal affiliation as an Emeritus Officer, which is listed on any publications and public talks I produce, and is shown on websites where I have editorial board memberships and the like – thus bringing some kudos to the university without any of that debasing business of having to provide me with a stipend. In a sense, I work for the University for free. (Which is fine by me – as I retired because of health concerns and now I work only 'as and when' I am feeling up to doing so, and as the muse inspires me.)
The proposed list of people to automatically have a cam.ac.uk email address includes Honorary Professors and Readers – but not Emeritus Officers. It also includes members of the University's governing body, the Regent House, of which I am currently a member. But that membership is not automatic for Emeritus Officers, and has to be renewed each year – again at the discretion of a head of institution (on a similar basis as is being proposed to retain email addresses).
At the moment, my own @cam.ac.uk email address is not under threat as I still have some research students yet to complete. Once they are finished, I would need to make a case for retaining my cam email address. At the moment it is suggested I would need to show I actively contribute to the academic life of the University or its Colleges. But if there is a very low bar on this, then heads of institutions are going to be doing a lot of paperwork. And if not, then what counts?
Regarding my College, Homerton College, in the past year I have attended a number of events (albeit virtual events): an on-line talk by a college fellow, a research seminar, and a briefing by a College Fellow to retired members on a potential change in teacher education policy. Do any of these count? Would they collectively count?
I've also been to some meetings in my Faculty where I am still have a profile page on the web as a retired professor (although I understand that strictly I am no longer a 'Member' of the Faculty in terms of being able to attend and vote at the annual meeting of the Faculty). Does going to a few seminars count as active involvement in the life of the University? And does the head of institution consider the broader picture – I have been to a number of on-line talks and seminars in the past year in other departments, so presumably they should count (if this is the kind of thing understood to count). After all, attending seminars and the like are a key part of the academic life of any university.
Indeed, since retirement I've been to more events in HPS (the Department of History and Philosophy of Science) than anywhere else. I'm listed on the departmental website as an 'affiliate' of the department – but that is a very informal association, so I am not sure if that in itself would count for anything in terms of 'activity'?
The proposed policy talks about self-nomination (to then be considered by the head of institution) of retired staff who consider themselves actively involved in defined activities of the collegiate University. Does 'defined' mean the applicant will be asked to define their involvement, or that there will be a list of defined activities as a guide to the heads of institutions? If the latter, then those defined activities remain very undefined at this point in time.
What should count as an allowed use of email communication through a University domain?
Leaving aside the question of who is entitled to have a University domain email address, there is the question of what it can be used for. The intention set out in the mooted policy is that those people with such email addresses should use them 'primarily' for their University work.
This seems a little akin to telling anyone who is living in University or College accommodation that they should only use that as their mailing address for academic correspondence, and use a separate postal address for any personal mail. Perhaps, even, that they should not be writing personal letters or addressing greetings cards sitting in their University accommodation.
That may seem a false analogy: after all, when you rent, or are perhaps in certain cases provided with, accommodation, then it is your home in which to live your life. Is anyone going to tell the head of a university house that they should have their family and non-College post sent to a P.O. Box where they can collect it, and only receive their college-related post at home? Of course not. (Indeed, their college related post should be reaching them via their office staff.)
That said, if that head of house was hosting noisy parties with intoxicated guests late into the night during the examination period then that would raise some eyebrows. Indeed, if the head of house was, in her own off-duty time, making and selling porn videos from the accommodation, or decided to decorate the walls with huge pro-Nazi posters of Adolf Hitler, then – even though this was activity in her home not her college office – this would likely be seen as completely inappropriate and unacceptable. That evaluation would not be because such things are private concerns and not academic activity: after all no one would object to her doing yoga, painting landscapes, or playing the clarinet in the college-owned house.
The point is that there are some things which can bring the University into disrepute, and they should not be done in a context that would be seen to be associated with the university (on its campuses, through its webpages, using its email domain) – even when they are things that are legal and which it is acknowledged members of the university community, as individuals, are free to chose to do even if others do not approve.
What about the students?
This seems especially an issue for student members of the university. They are given an email address and told it will be used for official communication, so they should check it regularly. But (under the proposed policy) they should not really be using that address to write home to parents or to arrange a group outing to the University's botanical garden. (Would it be a different matter if students on the natural science tripos arranged a trip to the botanic garden – or would they be able to use the address only as long as they were sure that most of the conversation at the garden would be plant-related?)
Getting a place at Cambridge is a pretty big thing for many students, so surely they should be proud of this aspect of their identity, and proud to use and give their @cam.ac.uk email address. What about those students from underrepresented groups – do we not want them emailing their friends back at school or college using their Cambridge email addresses?
Making a judgement
I thought it would be interesting to consider some of the email communication I have received via cam.ac.uk to consider what should still be allowed under the proposed policy. Of rather, what I would be expected to 'primarily' reserve my use of this email address for.
I will leave aside all those requests received for romantic relationships (from very attractive women who are happy to send me a photograph on request), bequests of millions, offers of drugs for sale, invoices and payment orders from organisations I have never heard of, and so forth, as clearly I would be very happy not to have this correspondence via any account. (What about those convincing-looking requests I sometimes get to reset my cam.ac.uk password? That seems to be University-related business?)
Emails with family are not university-related, and nor are messages about my household energy supply, or reminders to book an appointment at my dentist. I am on circulation lists from a number of outlets selling CDs, so I should be changing my registered email address there as well. And there are the discount book sellers – except that most of the books I buy are at least potentially related to areas I might write about. So, does that make them legit?
Emails with my current students would presumably be allowed – certainly when they ask for advice or I send them feedback on their writing. What about just general chit-chat with them, such as checking they are okay during the pandemic? That might be seen as part of a teacher's pastoral role – but officially in Cambridge that is meant to be the job of the college tutor not the supervisor. Officially, but surely all teachers have a level of pastoral responsibility, and you do not supervise someone's work for several years without having a concern for them as a whole person. And checking on their welfare or well-being surely contributes to their chances of successful completion, which is what the University wants? So, perhaps I can make a case for a blanket allowance there?
I am on a whole range of email lists related more-or-less directly to science teaching or to disciplines and activities linked to science education. Is it appropriate to use my Cambridge email for such discussion lists if they are linked to my work, even if much of the actual traffic on these lists turns out to be peripheral to my scholarship?
The academic life of the University – or of Academia?
This policy also raises issues the University might be best advised not to delve too deeply into. The work of an academic obviously usually includes teaching, associated administration and scholarship. But there is also the notion of 'service' to the wider community. This often concerns work undertaken for free, or for nominal payment, for other institutions. The University needs its academics to do this work, as it also relies on these kinds of contributions from academics elsewhere.
So, I get asked to referee work submitted for publication or grant applications. (Since I have retired, I feel empowered to decline most of this.) This is usually done for free, and without this type of activity the University would suffer as its own academics would not get their work reviewed. So, invitations of this kind should presumably(?) be considered as using email for academic and administrative work 'for' the University and the Colleges, even though the work is actually undertaken for journals and publishers and funding bodies.
The same applies to those requests to examine students (or programmes) at other universities, to evaluate proposals for tenure or promotion for other universities, to be involved in appointments panels for other institutions, to engage in external reviews or as external members of review panels (for courses, programmes, departments, etc.). Then there are requests to be members of committees, working parties, and the like for various professional and academic organisations like teaching associations and learned societies.
In all these cases, and many others like them, a person is approached to engage in some kind of activity for the good of the wider discipline/profession/society and they are invited because of their association with the University and/or because of their reputation related to their academic standing. In such cases the organisation making the approach would feel it reasonable to contact the person (and expect to receive a reply from them) as a member of the 'Cambridge' scholarly community, whether still in post or retired, and so would naturally expect to use a University email address. Such activities are considered positively – indeed expected – in cases for senior academic promotions in the University. Yet, strictly, none of this is academic or administrative work 'for' the University.
Another attack on academic standards?
As I mentioned above, when I first read the new proposed policy, it did not seem unreasonable. An @cam.ac.uk email address suggests an official affiliation and so acts as an assurance of a genuine link with the University. A university email is provided for business use and should not be used for private use.
The first point is fallacious. Any first year undergraduate could use their cam.ac.uk email address to pretend to be authorised to invite an external examiner, a visiting professor, to set up a research centre, or to order supplies of uranium. If they did, this would be fraudulent and a disciplinary matter. Anyone who took leave from their post elsewhere and arrived in Cambridge to spend a term as a visiting professor on the say-so of an invitation simply because it came from an @cam.ac.uk email would perhaps be entitled to feel cheated, but no court is going to consider the University responsible given the visitor's lack of due diligence.
So, removing cam.ac.uk emails from retired staff just in case they do something naughty that appears to be in an official capacity is a flawed argument. Given that most people with university email addresses in most universities are students, someone would have to be very stupid to trust that some approach was valid and authorised just because it came from such an email address. Indeed, even when you know the email address belongs to someone in a position of authority, that is no assurance that the account has not been hacked. (I've had those scam emails that seem to come from within the University. I imagine if I had responded on the basis the message seemed to be from the @cam.ac.uk domain I would quite rightly be considered foolish by the University.) Anyone who does anything of high significance on the basis of any unverified email message is naïve in the extreme.
Some people will do foolish or immoral and perhaps illegal things with whatever resources they have available to them – to therefore withdraw abusable resources from innocent members of the wider community just in case they do wrong is not a sensible approach to risk management. Certainly, it makes sense not to leave unattended and accessible things that are inherently dangerous – high explosive, concentrated sulphuric acid, loaded firearms… But a creative person looking to cause trouble could drown someone in a fire bucket, break windows and damage artworks with a fire extinguisher, and suffocate someone with a fire blanket. Even so, on balance, it makes sense to make these resources available to those members of a community using a University building.
The argument about only using the email domain for academic or administrative work for the University is also flawed. A member of the University should certainly not be running a commercial business through the @cam.ac.uk domain. But what is the problem if university students or staff (or retired staff) use their Cambridge email for social or personal emails as well as 'work'? The email domain is about identity – the person's identify as a member of the Cambridge University community. Sending a message via the email is no more claiming to be acting for the University than is writing a personal letter in a University flat, or an academic telephoning to arrange a plumber's visit on their office phone. The plumber would not assume that because the message came from a University telephone number the University will be paying for any work done at the academic's home.
"The mission of the University of Cambridge is to contribute to society through the pursuit of education, learning and research at the highest international levels of excellence."
The problem with the 'only for work' argument is it reduces the University to a business. It is not. (There may need to be a sense in which it is, as it needs to manage its financial affairs carefully, certainly, but it is not its purpose or prime nature.) Students are not employees, but matriculated members of the community. Teaching officers may be referred to by management as employees, but we need to remember who they work for: the University is a corporation of the Chancellor, Masters, and Scholars. The university is a network of scholars who come together to live and work in academic communities to share in a particular 'form of life'. Otherwise, how would it justify its charitable status?
"the opportunities for broadening the experience of students and staff through participation in sport, music, drama, the visual arts, and other cultural activities"
Universities encourage a 'form of life' that looks to develop the whole person – making it difficult to know what counts as the university's 'business'
For most scholars (student, teachers, retired) there is no sharp dividing line between the academic life and life more generally. Most social events involve talking shop because the academic community offers a form of life where people consider that they are doing something more than just earning a crust or boosting their c.v. Certainly, there is a consequent danger that people's work-life balance can go awry, but that is best avoided by us treating each other as members of the community and looking out for each other.
Is the business of these societies part of the 'business' of the university (or perhaps just those with a primarily academic focus)?
Otherwise, we surrender what is special about organisations like the University. What makes the community worth being a member of is the values that are (largely) shared – such as honesty, open-mindedness, fairness, enquiry, justice, the search for truth and authenticity, inclusivity, academic standards…
If we lose sight of that and just see the University as a(nother) business we are in danger of becoming no different to those organisations undermining scholarly norms (often criticised here) who will publish any nonsense for the right fee; who are happy to use false praise to entice contributions; who think lying in their communications is justified if it brings results. The University of Cambridge is a community of scholars (or perhaps a metacommunity of many entangled and overlapping communities of scholars), and it loses something very special if it starts to see itself as primarily a business, as transactional rather than relational.
A relational organisation says you have an email address in our domain because you have developed a relationship with us, and that identify remains when you retire as long as you wish to continue in, and properly respect, that relationship.
A transactional organisation says we gave you an email address in our domain when you worked for us, but now you are no longer contributing our cost-benefit analysis tells us we should withdraw it.
I think I know which impression the University should look to give.
Is it poor scientific practice to explain away results we would not expect?
Keith S. Taber
how convinced would be be by a student who found an increase in mass after burning some magnesium and argued that this showed that combustion was a process of a substance consuming oxygen as a kind of food
I came across an interesting account of an experiment which seemed to support a hypothesis, but where the results were then explained away to reject the hypothesis.
An experiment to test whether a lodestone buried in iron filings will get heavier
Experimental results always need interpretation
That might seem somewhat dubious scientific practice, but one of the things that becomes clear when science is studied in any depth is that individual experiments seldom directly decide scientific questions. Not only is the common notion that a positive result proves a hypothesis correct over-simplistic, but it is also seldom the case that a single negative result can be assumed to be sufficient to reject a hypothesis. 1
Given that, the reason I thought this report was interesting is that it was published some time ago, indeed in 1600. It also put me in mind of a practical commonly undertaken in school science to demonstrate that combustion involves a substance combining with oxygen. In that practical activity (commonly mislabelled as an 'experiment' 2), magnesium metal (for example) is heated inside a ceramic crucible until it has reacted, and by careful weighing it is found (or perhaps I should say, it should be found, as it can be a challenging practical for the inexperienced) that the material after combustion weighs more than before – as the magnesium has reacted with a substance from the air (oxygen).3 This is said to give support to the oxygen theory of combustion, and to be contrary to the earlier phlogiston theory which considered flammable materials to contain a substance called phlogiston which was released during combustion (such that what remains is of less mass than before).
Testing whether lodestones eat iron
The historical experiment that put me in mind of this involved burying a type of stone known as a lodestone in iron filings. The stone and filings were carefully weighed before burial and then again some months later after being separated. The hypothesis being tested was that the weight of the lodestone would increase, and there would be a corresponding decrease in the mass of the weight of the iron filings. Apparently at the end of the experiment the measurements, strictly at least, suggested that this was what had occurred. Yet, despite this, the author presenting the account dismissed the result – arguing that it was more likely the finding was an artifact of the experimental procedure either not being sensitive enough, or not having been carried out carefully enough.
Explaining away results – in science and in school laboratories
That might seem somewhat against the spirit of science – I wonder if readers of this posting feel that is a valid move to make: to dismiss the results, as if scientists should be fee to pick and chose which results they wish to to take notice of?
But I imagine the parallel situation has occurred any number of times in science classrooms, for example where the teacher responds to students' practical demonstrations that what is left after burning magnesium has less mass than the magnesium had before. Rather than seeing this as a refutation of the oxygen hypothesis (actually now, of course, canonical theory) – and possible support for the notion that phlogiston had been released – the teacher likely explains this away as either a measurement error or, more likely, a failure to retain all of the magnesia [magnesium oxide] in the crucible for the 'after' measurement.
Hungry magnets
The historical example is discussed in William Gilbert's book about magnetism, usually known in English as 'On the magnet'. 4 This is sometimes considered the first science book, and consists of both a kind of 'literature review' of the topic, as well as a detailed report of a great many observations and demonstrations that (Gilbert claims) were original and made by Gilbert himself. There were no professional scientists in 1600, and Gilbert was a physician, a medical practitioner, but he produced a detailed and thoughtful account of his research into magnets and magnetism.
Gilbert's book is fascinating to a modern reader for its mixture of detailed accounts that stand today (and many of which the reader could quite easily repeat) alongside some quite bizarre ideas; and as an early example of science writing that mixes technical accounts with language that sometimes seems quite unscientific by today's norms – including (as well as a good deal of personification and anthropomorphism) some very unprofessional remarks about some other scholars he considers mistaken. Gilbert certainly has little time for philosophers ('philosophizers') who set out theories about natural phenomena without ever undertaking any observations or tests for themselves.
Lodestones
Magnetism has been known since antiquity. In particular, some samples of rock (usually samples of magnetite, now recognised as Fe3O4) were found to attract both each other and samples of iron, and could be used as a compass as they aligned, more or less, North-South when suspended, or when floated in water (in a makeshift 'boat'). Samples of this material, these naturally occurring magnets, were known as lodestones.
Yet the nature of magnetism, seemingly an occult power that allowed a stone to attract an iron nail, or the earth to turn a compass needle, without touching it, remained a mystery. Some of the ideas that had been suggested may seem a little odd today.
Keepers as nutrients?
So, for example, it is common practice to store magnets with 'keepers'. A horseshoe magnet usually has a steel rod placed across its ends, and bar magnets are usually stored in pairs with steel bars making a 'circuit' by connecting between the N of one magnet with the S of the other. But why?
One idea, that Gilbert dismisses is that the magnet (lodestone) in effect needs a food source to keep up its strength,
"The loadstone is laid up in iron filings, not that iron is its food; as though loadstone were alive and needed feeding, as Cardan philosophizes; nor yet that so it is delivered from the inclemency of the weather (for which cause it as well as iron is laid up in bran by Scaliger; mistakenly, however, for they are not preserved well in this way, and keep for years their own fixed forms): nor yet, since they remain perfect by the mutual action of their powders, do their extremities waste away, but are cherished & preserved, like by like."
Gilbert, 1600 – Book 1, Chapter 16.
Girolamo Cardano was an Italian who had written about the difference between amber (which can attract small objects due to static electrical charges) and lodestones, something that Gilbert built upon. However, Gilbert was happy to point out when he thought 'Cardan' was mistaken.
An experiment to see if iron filings will feed a magnet
Gilbert reports an experiment carried out by Giambattista della Porta. Porta's own account is that:
"Alexander Aphrodiseus in the beginning of his Problems, enquires wherefore the Loadstone onely draws Iron, and is fed or helped by the fillings of Iron; and the more it is fed, the better it will be: and therefore it is confirmed by Iron. But when I would try that, I took a Loadstone of a certain weight, and I buried it in a heap of Iron-filings, that I knew what they weighed; and when I had left it there many months, I found my stone to be heavier, and the Iron-filings lighter: but the difference was so small, that in one pound I could finde no sensible declination; the stone being great, and the filings many: so that I am doubtful of the truth."
Porta, 1658: Book 7, Chapter 50
Gilbert reports Porta's experiment in his own treatise, but adds potential explanations of why the iron filings had slightly lost weight (it is very easy to lose some of the material during handling), and why the magnet might be slightly heavier (it could have become coated in some material during its time buried),
"Whatever things, whether animals or plants, are endowed with life need some sort of nourishment, by which their strength not only persists but grows firmer and more vigorous. But iron is not, as it seemed to Cardan and to Alexander Aphrodiseus, attracted by the loadstone in order that it may feed on shreds of it, nor does the loadstone take up vigour from iron filings as if by a repast on victuals [i.e., a meal of food]. Since Porta had doubts on this and resolved to test it, he took a loadstone of ascertained weight, and buried it in iron filings of not unknown weight; and when he had left it there for many months, he found the stone of greater weight, the filings of less. But the difference was so slender that he was even then doubtful as to the truth. What was done by him does not convict the stone of voracity [greediness, great hunger], nor does it show any nutrition; for minute portions of the filings are easily scattered in handling. So also a very fine dust is insensibly born on a loadstone in some very slight quantity, by which something might have been added to the weight of the loadstone but which is only a surface accretion and might even be wiped off with no great difficulty."
Gilbert, 1600 – Book 2, Chapter 25.
Animistic thinking
To a modern reader, the idea that a lodestone might keep up its strength by eating iron filings seems very fanciful – and hardly scientific. To refer to the stone feeding, taking food, or being hungry, is animistic – treating the stone as though it is a living creature. We might wonder if this language is just being used metaphorically, as it seems unlikely that intelligent scholars of the 16th Century could actually suspect a stone might be alive. Yet, as Gilbert points out, there was a long tradition of considering that the lodestone, being able to bring about movement, had a soul, and Gilbert himself seemed to feel this was not so 'absurd'.
A reasonable interpretation?
We should always be aware of the magnitude of likely errors in our measurements, and not too easily accept results at the margins of what can be measured. Gilbert's suggestions for why the test of whether mass would be transferred from the iron to the magnet might have given flawed positive results seem convincing. It would be easy to lose some of the filings in the experiment: especially if the "heap of Iron-filings" was left for several months without any containment! And the lodestone could indeed easily acquire some extraneous material that needed to be cleaned off to ensure a valid weighing. As the lodestone attracts iron, all of the filings would need to be carefully cleaned from it (and returned to the 'heap' before the re-weighing).
But, I could not help but wonder if, in part at least, I found Gilbert's explaining away of the results as reasonable, simply because I found the premise of the iron acting as a kind of food as ridiculous. We should bear in mind that although the predicted change in mass was motivated by a notion of the magnet needing nutrition, that might not be the only scenario which might give rise to the same prediction. 1 After all, how convinced would be be by a student who
suggested combustion was a process of a substance consuming oxygen as a kind of food, and
therefore predicted that magnesium would be found to have got heavier after a good meal, and
subsequently found an increase in mass after burning some magnesium, and
argued that this gave strong support for the oxygen-as-food principle?
Coda
It is rather difficult for us today to really judge how language was used centuries ago. Do these natural philosophers talking of magnets eating iron mean this literally, or is it just figurative – intended as a metaphor that readers would understand suggested that there was a process somewhat akin to when a living being eats? 5 Some of them seemed quite serious about assigning souls to entities we today would conspire obviously inanimate. But we should be careful of assuming apparently incredible language was meant, or understood, literally.
In the same week as I was drafting this posting I read an article in Chemistry World about how the heavier elements are produced, which quoted Professor Brian Metzer, physicist at Columbia University,
"What makes the gamma-ray burst in both of these cases [merging neutron stars and the collapse of large rapidly rotating stars] is feeding a newly-formed black hole matter at an extremely high rate…The process that gives rise to the production of this neutron-rich material is actually outflows from the disc that's feeding the black hole."
Brian Metzer quoted in Wogan, 2022
If we would be confident that Professor Metzer meant 'feeding a black hole' to be understood figuratively, we should be careful to reserve judgement on how the feeding of lodestones was understood when Porta and Gilbert were writing.
Sources cited:
Gilbert, W. (1600/1900). On the Magnet, Magnetick Bodies also, and on the great magnet of the earth; a new physiology, demonstrated by many arguments & experiments (S. P. Thompson, Trans. Project Gutenberg ed.). [Available as a free e-book at https://www.gutenberg.org/files/33810/33810-h/33810-h.htm]
Wogan, T. (2022, 5th Janaury 2022). How elements are made beyond the stars. Chemistry World, 19, 28-31.
Notes:
1 Strictly scientific tests never 'prove' or 'disprove' anything.
The notion of 'proof' is fine in the context of purely theoretical disciplines such as in mathematics or logic, but not in science which tests ideas empirically. Experimental results always underdetermine theories (that is, it is always possible to think up other theories which also fit the results, so a result never 'proves' anything). Apparently negative results do not refute ('disprove') a theory either, as any experimental test of a hypothesis also depends upon other factors (Has the researcher been sloppy? Is the measuring instrument valid – and correctly calibrated? Are any simplifying assumptions reasonable in the context…). So experimental results offer support for, or bring into question, specific theoretical ideas, without ever being definitive.
2 An experiment is undertaken to test a hypothesis. Commonly in school practical work 'experiments' are carried out to demonstrate an accepted principle, such that it is already determined what the outcome 'should' be – students may have already been told the expected outcome, it appears i n their textbooks, and the title of the activity may be suggestive ('to show that mass increases on combustion'). Only if there is a genuine uncertainty about the outcome should the activity be labelled an experiment – e.g., it has been suggested that combustion is like the fuel eating oxygen, in which case things should be heavier after burning – so let's weigh some magnesium, burn it, and then re-weight what we have left (dephlogisticated metal?; compound of metal with oxygen?; well-fed metal?)
3 Mass and weight are not the same thing. However, in practice, measurements of weight made in the laboratory can be assumed as proxy measurements for mass.
4 As was the norm in European scholarship at that time, Gilbert wrote his treatise in Latin – allowing scholars in different countries to read and understand each other's work. The quotations given here are from the 1900 translation into English by S.P. Thompson.
5 Such metaphors can act as communication tools in 'making the unfamiliar familiar' and as thinking tools to help someone pose questions (hypotheses?) for enquiry. There is always a danger, however, that once such figures of speech are introduced they can channel thinking, and by providing a way of talking about and thinking about some phenomena they can act as obstacles to delving deeper in their nature (Taber & Watts, 1996).
I recently listened to NASA's Nicky Fox being interviewed about the Parker Solar Probe which (as the name suggests) is being used to investigate the Sun.
There is a website for the project which, when I accessed it (28th December 2021), suggested the spacecraft was 109 279 068 km from the Sun's surface (which I must admit would have got a marginal comment on one of my own student's work along the lines "is the Sun's surface so distinctly positioned that this level of precision can be justified?") and travelling at 57 292 kph (kilometers per hour). This unrealistic precision derives from the details being based on "mission performance modeling [sic] and simulation and not real-time data…" Real-time data is not necessarily available to the project team itself – the kind of shielding needed to protect the spacecraft from such extreme conditions also creates a challenge in transmitting data back to earth.
But the serious point is that returning to the website at another time it is possible to see how the probe's speed and position have changed (as shown on 'the Mission' webpage – indeed by the time I took the 'screenshot' it had moved about 7000 km), as the spacecraft moves through a sequence of loops in space orbiting the Sun on a shifting elliptical path that takes it periodically very close (very close, in solar system terms, that is) to the sun. Like any orbiting body, the probe will be moving faster when closest to the sun and slowest when furthest from the sun. (The balance shifts between its kinetic and potential energy – as it works to move away against the sun's gravity when receding from it 1.)
Touching the Sun
Publicity still from the Danny Boyle film 'Sunshine'
Getting too close the Sun – with its high temperature, the 'solar wind' of charged particles emitted into space, occasional solar flares, and the high flux of radiation from across the electromagnetic spectrum – is very dangerous, making the design and engineering of any craft intended to investigate our local star up close very challenging. A key feature is a protective heat shield facing the Sun . This was the premise of the sci-fi film 'Sunshine' 2.
For the Parker probe
"the spacecraft and instruments will be protected from the Sun's heat by a …11.43 cm carbon-composite shield, which will need to withstand temperatures outside the spacecraft that reach nearly …1,377 degrees Celsius"
"At closest approach to the Sun, while the front of Parker Solar Probe' solar shield faces temperatures approaching … 1,400° Celsius, the spacecraft's payload will be near room temperature, at about [29ËšC.]."
http://parkersolarprobe.jhuapl.edu
Note: Dr Fox is NOT reporting from the Parker Solar Probe – just pictured in front of an image of the sun (Dr Fox's profile on NASA website)
Dr Fox, who is Director of NASA's Heliophysics [physics of the Sun] Division, was being interviewed about data released from an earlier close approach on a BBC Science in Action podcast.
"The Parker Solar probe continues its mission of flying closer and closer to the sun. Results just published show what the data the probe picked up when it dipped into the surrounding plasma. NASA's Nicky Fox is our guide."
The project is framing that event as when, "For the first time in history, a spacecraft has touched the Sun". Although the visible surface of the sun has a temperature of about 6000K (incredibly hot by human standards), the temperature of the 'atmosphere' or corona around it is believed to reach several million Kelvins. On the programme, Dr Fox was asked about how the spacecraft could survive in the sun's corona, given its extremely high temperatures.
A teaching analogy?
In response she used an analogy from everyday experience:
"We talk about the plasma being at a couple of million degrees, it's like putting your hand inside an oven, and you don't touch anything. You won't burn your hand, you'll feel some heat but you won't actually burn your hand, and so the solar wind itself, or the corona, is a very tenuous plasma, there are just not that many particles there. So, even though the whole atmosphere is at about two million degrees, the number of particles that are coming into contact with the spacecraft are [sic] very small.
The temperatures that we have to deal with are about fourteen, fifteen hundred degrees Celsius, at the maximum, which is still hot, don't…let me kid you, that's still hot, but it is not two million degrees."
Dr Fox interviewed on Science in Action
Analogies are commonly used in science, science communication and science education as one means of 'making the unfamiliar familiar' by showing how something novel or surprising is actually like something the audience is already aware of and comfortable with.
If the probe had been dipped in a molten vat of some hypothetical refractory liquid at two million degrees it would have quickly been destroyed. But because the Corona is not only a plasma (an 'ionised gas')3, but a very tenuous one, this does not happen. NASA sending the probe into the corona is similar to putting one's hand in the oven when cooking. If you touch the metal around the outside you will burn yourself, but you are able to reach inside without damage as long as you do not touch the sides – as although the air in the oven can get as hot as the metal structure, it has a very low particle density compared with a solid metal. So, your hand is in a hot place, but is not in contact with much of the hot material.
Do not try this at home – at least not unless you are quick
Of course, this is not the whole story. You can reach in the oven to put something in or (with suitable protection) take something out, but you cannot safely leave your hand in there for any length of time.
When two objects at different temperature are placed in contact, heating will occur with 'heat' passing from the hotter to colder object until they are in thermal equilibrium (i.e., at the same temperature). But this is not instantaneous – it takes time.4 If the Parker Solar Probe had been flown into the Sun's atmosphere and left there it would have been heated till it eventually matched the ambient temperature (not 'just' 1400ËšC) regardless of how effective a heat shield it had been given. Or rather, it would have been heated till its substance reached the ambient temperature, as it would have lost structural integrity long before this point.
Of course, the probe has been designed to spend some time in the coronal atmosphere collecting data, but to only dip in for short visits, as NASA is well aware that it would not be wise to leave one's hand in the oven for too long.
Note:
1 This at least is the description based on Newtonian physics. There is an attractive, gravitational force between the Sun and the probe. As the spacecraft moves towards the sun it accelerates, and then its momentum takes it away, being decelerated by gravity.In this model gravity is a force between two bodies. (The path is actually more complex than this, as it has been designed to fly past Venus several times to adjust its trajectory round the Sun.)
In the model offered by general relativity the probe simply moves in a straight line through space which has a complex geometry due to the presence of matter/energy: a straight line which seems to us to be a shifting series of ellipses. Gravity here is best understood as a distortion from a 'flat' space. Perhaps it is clear why for most purposes scientists stick with the Newtonian description even though it is no longer the account considered to best describe nature.
2 The movie poster gives a slight clue to the hazards involved in taking a manned mission to the Sun!
3 Plasma is considered a fourth state of matter: solid, liquid, gas, plasma. The expression that 'a plasma is an ionised gas' may suggest plasma is a kind of gas, but then we might also say that a gas is a boiled liquid or that a liquid is melted solid! So, perhaps what we should say is that a plasma [gas/liquid] is what you get when you ionise [boil/melt] a gas [liquid/solid].
4 In theory, modelling of such a process suggests it takes an infinite time for this to occur. 5 In practice, the temperatures become close enough that for practical purposes we consider thermal equilibration to have occurred.
5 This is an example of a process that can be understood as having a negative feedback cycle: temperature difference drives the heat flow, which reduces temperature difference, which therefore also reduces the driver for heat flow; so the rate of heat flow is reduced, so therefore the rate of temperature change is reduced… This is a similar pattern to radioactive decay – both follow an 'exponential decay' law.
