More (un)certainty, or do I mean something else?

Following on from my last blog, the event on poetry and astronomy at Royal Observatory in Greenwich went very well. Jocelyn Bell Burnell gave a great talk and invited members of the audience to read aloud the poems on astronomy she had selected. These readings were fantastic; and I think helped the discussion with the audience to flow more freely.

At one point during this discussion I said that perhaps scientists aim to be more ‘certain’ in their writings than poets, and aim to get a more definite response in their readers. A lady in the audience rightly reminded me that since 1927 physicists have been wrestling with uncertainty, and in particular the uncertainty principle and its implications for reality.

One of the problems with trying to understand the uncertainty principle is the word ‘uncertainty’. It’s a translation from the original German phrase used by Heisenberg when he formulated the physics. But he actually used several German words. It’s a shame that the English equivalent has invariably been ‘uncertainty’ and perhaps we accord that specific word too much weight.

What Heisenberg actually deduced, and what he summarised in this principle, is that not every physical property of a system exists with infinite precision at every point in time. Furthermore, these physical properties are connected; so that the more precise the position of a particle is, the less precise is its momentum.

You often see this explained as due to the practical problems of measurement; if you measure the position of a particle, you use light photons to do this and they will hit the particle, inevitably leading to a change in its momentum. This way of thinking implies that there is an underlying physical certainty, but that we just can’t measure it. It leads to approximately the right mathematical formulation of the principle, but it’s wrong-headed. It’s a metaphor that’s been stretched too far.

The uncertainty principle is telling us something much more fundamental about reality than that. It’s telling us that reality itself has an inexactness; there is nothing beyond what we can measure. There is no underlying, more precise, reality. This can perhaps be better expressed in some of the other words that Heisenberg used, for example; ‘indeterminability’.

So, some of the misunderstandings about this principle derive from the English word ‘uncertainty’, and the fact that this translation of Heisenberg’s original words has become rather too crystallised, perhaps even too ‘certain’. It’s taken on a shorthand meaning of a general vagueness, and even a general limit to scientists’ ambitions about their work.

An additional layer of uncertainty has been added by the requirement to translate Heisenberg’s words from German, and this influences the way we’re able to discuss the subject in English. (It’s obviously more precise to go to the maths, but there was an analogous ‘translation’ problem in the 1920s, when both Heisenberg and Schrödinger came up with very different mathematical formulations for quantum physics. It took some time before they realised that one formulation could be translated into another.)
Is it easier to talk about this principle in the original German? Answers on a postcard, please.

Finally, there will be more actual (as opposed to online) discussions about poetry and science; we’re having a ‘social sessions’ event on 13 January in Edinburgh at the Scottish Poetry Library. Do come!

Dark matter – clear poetry

The Royal Observatory Greenwich is holding a public event on 10 November to discuss poems about astronomy. The astronomer Dame Jocelyn Bell Burnell, the poet Kelley Swaine, and I will be speaking at it.

There is a lot of poetry written about astronomy, and I find this surprising for a couple of reasons.

First, because there’s hardly any literary fiction (I’m only singling out literary fiction because, with its emphasis on language, it’s the nearest thing in prose to poetry) inspired by astronomy. There are the wonderful books by John Banville, ‘Copernicus’, and ‘Kepler’, which are fictional accounts of these astronomers’ lives. There is ‘The Discovery of Heaven’ by Harry Mulisch. And that’s it. (Is it? Tell me I’m wrong)

Second, poetry likes to restrict itself in terms of space, and numbers of words. It likes to be concise, condensed. Astronomy, by its very nature, attempts to explain the entire universe. How can there be any sort of dialogue between such a constrained art-form and such a sprawling subject? What can poetry meaningfully say about astronomy?

Looking at the anthology of poetry about astronomy, ‘Dark Matter’, what strikes me is how many of the poems use people to investigate the subject. As I’ve said before in previous blogs we can’t seem to escape the human-sized in literature. So is astronomy just being used as a metaphor for human activities and emotions? Or is it being explored as something interesting in its own right?

Rebecca Elson managed to write very concise poems that convey an accurate sense of the science – her poem ‘Explaining Relativity’ describes how, according to the theory of general relativity, space is distorted by matter, and the way matter moves is correspondingly affected by this distortion.
‘What if There Were No Moon?’ describes how the Moon affects the Earth; not only tides and eclipses, but also human constructions such as the calendar.

Perhaps poetry has similarities to mathematics, in that discipline’s desire to explain and describe as concisely as possible. Euler’s identity is much loved by mathematicians, because it links the fundamental arithmetic operations to irrational, transcendental, and imaginary numbers in one very simple equation. e to the i pi plus one equals zero. When you say it out loud it sounds like poetry.

Why we should resist the urge to classify everything

Recently James Kelman has been letting off steam about the fact that genre fiction outsells literary fiction and is far more likely to be reviewed in the so-called literary supplements of the newspapers. But both he and many of the people commentating on his criticisms seem to have a curiously simple-minded approach to the literary vs. genre debate. Literary is deemed to be automatically more virtuous or ‘good’ because the author is not subject to any external demands or limitations in terms of style or content, and genre is the bad guy because it apparently doesn’t question or subvert the readers’ expectations. But how much ‘literary’ fiction does actually subvert, or at least stretch, those expectations? And how much of it seems to be in thrall to style, at the expense of content or plot? Many writers sneer at so-called ‘plot-driven’ genre. But just what is wrong with plot? Why are books with more character development than plot lauded over genre?

Writers don’t just write genre fiction because they want to sell. They write it because they have something to say that can’t be fit into the expectations of literary fiction. Despite what Kelman et al. say, literary fiction regularly excludes from itself books whose quality of writing, or ‘style’, certainly justifies their inclusion. It does so because it’s uncomfortable with the subject matter. For example, Margaret Atwood says her books are not science fiction, because the latter only addresses what has not yet happened. This arbitrary definition gives the lie to literary fiction being less rigid in its expectations than (other) genre.

Caster Semenya’s plight may read like a science fiction novel, but it’s real.
Until her story hit the news, I assumed that females were created by two X chromosomes being present in the foetus, and males by one X and one Y. But this is not so. It seems that a person’s sex is a complex physical phenomenon which arises from an interaction between chromosomes and hormones. In order for the chromosomes to have the expected effect on the development of the organism, they need to be supported by the relevant hormones, in the right quantities at the right times.

For example, a person with XY chromosomes can only develop as a male if their body is receptive to the androgen hormones. If they have a condition known as androgen insensitivity syndrome, they will develop as a female, despite the presence of a Y chromosome in their bodies. So, while most people’s sexes are straightforward to categorise, a minority exist on a continuum in between the two most common ‘extremes’.

It seems to be impossible to decide ‘objectively’ the point on this continuum at which ‘female’ can be differentiated from ‘male’, without asking the person concerned what sex they feel they are. That is why Caster Semenya is undergoing psychological tests, as well as physiological ones.

This sort of psychological test sounds depressingly similar to those foisted on gay people in the past, but at least it may give Caster some input into the decision that the IAAF are going to make about her sex.

Classification of people (and of writing) is all well and good if it gives us genuine insights into the world. But if classifications make our thinking too rigid and become uncoupled from reality, then we should learn to live without them.

Tiny galaxies, enormous atoms, and people at the centre of it all...

Literary fiction usually only portrays human characters. This type of fiction places humans at the centre of what is an inhuman universe. It hasn’t absorbed the lesson of the Copernican revolution.

In contrast, since Copernicus’s models and Galileo’s observations, science thinks it fully understands that the universe was not built for us (leaving aside any discussion of the anthropic principle - I’ll save that for another day).

Science deals with physical and temporal phenomena on all scales. The way we define a second of time uses gaps between energy levels in atoms. Stars and galaxies were created billions of years ago.

But I wonder if scientists still sneakily use humans and human-sized experiences as the ultimate measuring scale.

It’s common in astronomy to use redshift as a proxy for distances to galaxies. This is because redshift is the only direct measurement of distance without any reference to, or reliance on theoretical models of the universe. But it also happens to be a simple number without any units (because it is a ratio), and for all measurements apart from one, it is currently between 0 and 10. The only redshift measurement which is higher than this is for the cosmic microwave background, which is at a redshift of 1000.

So, when you’re at a telescope, measuring the redshifts of quasars, you don’t think about the fact that they were formed billions of years ago and are billions of light-years away (the word ‘are’ is a bit tricky in this context – you’re seeing them as they were then, not as they are now). They have redshifts of 1, 2, 3, 4 – numbers you learnt in primary school.

The same goes for size. Astronomers look at images of galaxies that are small enough to fit onto their computer screen. They used to use glass plates to take images of large parts of the sky. Just one of these plates, which are 8 inches square, would show around 100,000 objects – both stars and galaxies. So there was a curious inversion of size, we had to look at these plates with an eyepiece to see the details of the galaxies, the curved spiral arms, the wisps of gas. In every single astronomical imaging there is a huge compression ratio of what is actually out there to what we can cope with.

The list goes on and on… Physicists use a unit called a ‘barn’ to refer to the cross section of an atomic nucleus. When this was first calculated in the 1940s, people said that it was ‘as big as a barn door’.

There is a lovely poem on the Human Genre Project which compares the images of chromosomes to teeth. Again – bringing the not quite human into our world.

Are there drawbacks to this? It means the Copernican revolution is not finished. So when Richard Dawkins tries to explain to us that our behaviour is governed by genes, we still cannot accept that loss of free will. And while science is still struggling, literary fiction hasn’t even begun to come to terms with this.

Madame Curie's transformation

My favourite essay in ‘The Faber Book of Science’ (edited by John Carey) is ‘Shedding Life’ by Miroslav Holub, who is a poet and immunologist. In this essay he recollects mopping up the blood of a recently shot muskrat, and he ponders on the exact nature of death. The death of an organism as a whole is generally taken to be defined as brain death or heart failure. But what about all the constituents of that organism? Holub points out that many of these; blood cells, hormones, enzymes etc., are all capable of living on for some time after the apparent death.

When Marie Curie died (in 1934) her belongings, such as her note books, were discovered to be so radioactive that they had to be deposited in lead-lined boxes. Even now, anyone who wants to look at them has to wear protective clothing.
She died of cancer, most likely caused by a lifetime of working with radioactive substances without being properly protected from the resulting radiation. Her most famous achievements were to discover new chemical elements, by virtue of the fact that they were radioactive. In making these discoveries she helped to shed light on the nature of radioactivity, and show that there are three different types; alpha, beta and gamma radiation. When an element emits or absorbs alpha or beta particles it changes into another element. This is why the study of radioactivity has been considered to be a sort of alchemy. (You can get gold from radioactive mercury, but it is very difficult).

Marie Curie worked with a uranium ore called pitchblende, exposing herself to alpha particles, and to radon gas. Both of these would have been absorbed by her body, causing damage to the cells. At an atomic level some of the alpha particles may have been absorbed by the atoms in the cells (Humans are carbon-based and so most of these atoms are carbon atoms. The process of carbon atoms absorbing alpha particles and transmuting into oxygen atoms is what happens in dying stars.)
Radon gas has a long half life but eventually decays into polonium, one of the elements Marie Curie is famous for discovering and which she named after the land of her birth; Poland. Polonium is called a ‘daughter product’ of radon as a result of this process.
Her body is interred in the Pantheon in Paris. It is still radioactive; alongside the more usual organic decay processes taking place there are also the atomic ones. She is being transmuted herself.

Intuition about mice and quasars

‘Intuition’ (by Allegra Goodman) takes place in a cancer research lab where one of the junior workers, Cliff, thinks he’s found a virus which can cure cancer in mice. The lab is in financial trouble, so its directors are grateful for the chance to publicise these results and use them to raise funds. However, it proves impossible to replicate the results, and another post-doc, who happens to be Cliff’s ex-girlfriend, suspects him of fraud.

Some reviews of this book have suggested that it’s never made entirely clear whether Cliff has knowingly committed fraud, or if he has unwittingly made a mistake. But there is a clue quite late on, when we get a glimpse of Cliff’s reasoning;

‘He had not chosen to discuss every piece of data, but had run ahead with the smaller set of startling results he’d found. Still, aspects of his data were so compelling that in his mind they outweighed everything else. He had sifted out what was significant and the rest had floated off like chaff.’

From a scientific point of view, the first sentence of this quote is damning. Cliff just doesn’t seem to be a very good scientist. When you run an experiment you cannot pick and choose where your results start and end. If you start with a hundred mice, you must discuss the results of the experiment on all of those mice, not just the few that happen to show a good result. This is because there’s always the possibility that your good result happened by chance. If you spot a good looking result in a subset of your data, it may just be a random fluctuation. (That is also true of the whole dataset, of course, and should be quantified as far as possible.)

It’s bad science to select a subgroup of interesting results after the event, but it’s depressingly common. When I was an astronomer, I worked on quasars. There’s a so-called ‘controversy’ about whether or not these objects are at the incredibly large distances as implied by their redshifts, if the Big Bang model is correct. This controversy was a genuine problem when quasars were first discovered in the sixties, but has now fizzled away. Only a few ‘maverick’ astronomers, such as Halton Arp, now believe quasar redshifts aren’t cosmological. The controversy is an artefact of only choosing the data that fit the hypothesis and ignoring all the other data, in this case of looking at quasars that appear to be near to much lower redshift galaxies. Statistically this doesn’t happen any more than you would expect – but superficially it looks ‘interesting’.

One nice aspect of ‘Intuition’ is that the point of view is omniscient and no one character is particularly favoured; rare in modern literature. The reader gets to inhabit the minds of all the major characters and understand their view of the drama unfolding around them. Even so, with all this information that we are provided, it proves impossible to understand the reasons behind the characters’ actions.

This failure of the omniscient narrator to get to the truth of the matter could be read as a warning – are we deluded in hoping/expecting science to be an impartial tool for understanding the external world? Or am I confusing science with omniscience?

Madame Bovary on a beam of light

I’ve been rereading ‘Madame Bovary’ and am struck, all over again, at how Flaubert lets us draw our own conclusions about Emma Bovary’s actions, without forcing any ‘morals’ down our throats.
Flaubert was one of a set of nineteenth century writers, along with others such as Zola, who were very influenced by the rise in science and who saw himself as a sort of human and/or social experimenter. Many other writers have also consciously seen themselves in this way. Brecht commented that he conducted experiments on audiences with his dramas and spoke of turning the theatre into a laboratory.

‘Copenhagen’ by Michael Frayn can be seen as an experiment in the way it repeats variations of the real-life conversation between Heisenberg and Bohr in 1941 in Nazi-occupied Copenhagen, in a repeated attempt to understand what really happened at this meeting. But, literature isn’t really the same as an experiment? In ‘Copenhagen’ the audience is presented with different versions of the events but we never get to understand what really happened, and why. But that’s not the aim of this particular experiment. What we’re left with is an understanding that it is fundamentally impossible to know what happened that night in Copenhagen, despite all the written records.
That understanding is a satisfactory result of this dramatic experiment. It doesn’t matter that this experiment cannot really happen, that it’s only acted out for us. It’s actually a perfect example of a thought experiment.

Thought experiments have a long pedigree in science. They’re best characterised as hypothetical experiments which we can imagine, but which we’re not able to perform. They allow us to set up a scenario and think through the repercussions. Einstein, influenced by the philosopher and physicist Ernst Mach, was a whiz at developing thought experiments. Some of the best ones (such as imagining a person riding on a beam of light) show how his theories developed from considering everyday objects such as clocks and rulers. They also provide the most accessible illustrations of the ramifications of his theories, without having to wade through all the maths.

As twentieth century physics became more esoteric and abstruse, physicists became more and more reliant on thought experiments to illustrate the implications of their work.
The most famous of these thought experiments; Schrodinger’s cat, was developed as a reductio ad absurdam by Schrodinger to criticise the bizarre, and clearly to him wrong headed, ‘standard’ interpretation of quantum physics. In this experiment a cat is locked in a box with a vial of poison. After a fixed amount of time, depending on a random process, the cat will either be killed by the poison, or not. But according to quantum physics, until we open the box, observe the cat, and therefore measure the outcome of the experiment; the cat is in a superposition of quantum states and is both dead and alive.

This experiment is not about to be performed in any laboratory soon. It doesn’t need to be. Thought experiments are a beautiful use of imagination in science. They allow the scientist to imagine ‘what if?’ This is precisely the question that fiction writers ask. Just because the results aren't scientifically provable doesn't mean they're not true.