Monday, 7 March 2011

Entropy

Last night I was watching the first programme in Brian Cox's new BBC series Wonders Of The Universe. In it, he was examining the question of the “Arrow of Time”, and “Entropy”. I'm sure that physicists understand this much better than I do, but on the basis of the argument put last night, I'm far from convinced.

Brian began by examining the arrow of time by looking at ice falling from a glacier into the sea. There is no physical reason he said why the picture we see could not be reversed. That is that we see a wave coming in, and ice jumping out of the water and attaching itself to the glacier. We don't see that happen, he argued because the probability of it happening that way around is far smaller. Fair enough, I thought at the time, though I thought the argument was a bit false, because the laws of physics most particularly of gravity are precisely what makes it less likely. However, my wife reminded me this morning about a news story over Christmas, about an ice scultpture that had spontaneously formed on a lighthouse, precisely because water had splashed up from waves, and in the freezing temperatures had solidified and attached itself to the lighthouse. That made me consider that what is or is not more or less probable, does indeed dependend upon the material conditions existing within the specific case.

He went on to explain this probability in terms of Entropy. The example he gave was of a pile of sand. Pick up a handful of sand from this pile, and toss it back, and the basic structure of the pile is unchanged. That is because there are trillions of combinations in which the grains of sand can be organised, and still leave the pile looking exactly the same. However, take the same amount of sand, and give it order and structure by moulding it into a sand castle, and this is no longer true. Take a handful and drop it and it no longer looks like a sandcastle, the particular order and structure has been disrupted. That is he says because the probability of the grainbs of sand simply falling back to how they were is very low.

But, I have to say I am not at all convinced by this argument on philosophical grounds for various reasons. Firstly, the concept of order and structure is a human concept. It is an idea that humans have created to enable us to make sense of the world around us. That is why even in things that are unordered and unstructured, the human brain attempts to provide that organisation and structure, by ralating what we see to something that is organised and structured that we recognise. It is why we are fooled by optical illusions, for instance. When we look at a sandcastle, we see organisation and structure because it is something that has been deliberately created to have what we call organisation and structure, and resembles other things, houses, castles etc. whereas in fact all it really is, is a pile of sand. In fact, our brain is so attuned to seeing organisation and structure that even if you knock most of the sand castle down, we will still recognise it as a sand castle.

On the other hand, we see the pile of sand, and do the same thing, we equate it to a hill, a pyramid, or something that also has form and structure. Pick up a pile of sand and drop it, and it still looks the same. But, of course, it is not the same, any more than the sand castle was the same after the procedure. If you were an ant climbing the pile, you might notice a considerable difference to the pile after it has been reorganised, for instance. It is only because our brains are attuned to looking at things at a superficial level that we conclude that nothing has really changed that we make this rash conclusion. Consider a cloud. People often say they can see a face in clouds. Does the fact, that this cloud is formed in such a way that it creates the image of something we are familiar with, something we consider to have form and structure – a face – mean that this cloud DOES have more form and structure than any other cloud? No, of course not.

The point of the argument was that, precisely because it is less likely for matter to be organised and structured than to be chaotic, there will be a natural tendency for matter to move from being ordered and structured to being chaotic. But, I have to say that looking at the nature of reality, I would say that you could find at least as many instances where the opposite is the truth. If we start from the Big Bang, then we have a spewing out of an almost infinitely large number of sub-atomic particles. The probability that these particles might form themselves together in some form of more complex structure is indeed, extremely low. So low, in fact, that in order to make the mathematical models of the Universe work, physicists have had to come up with the idea of the multiverse to explain the existence of the Universe we live in! But, that brings us back to the point about what is probable or improbable being determined by the precise conditions that exist in the particular case. In an infinite number of Universes within the multiverse, so the argument goes, the laws of physics and so on will not lead to the coming together of atoms and molecules, will not lead to gravity bringing together clunps of matter to form stars, planets, galaxies and so on. In our particular, Universe, and an infinite number of otehrs like it, those conditions will hold, however, improbable.

The probability is much greater that all of the myriad sub-atomic particles created at the moment of the Big Bang would have simply acted chaotically, sped off into space never to be seen again. But, in fact, they didn't, or at least a large number of them didn't. Instead out of the chaos and formlesness of the Big Bang came order and structure! Particles came together to form more complex particles, and more complex structures, as many as 12 different dimensions existing at the time of the Big Bang, were formed into some kind of order and rationality in the shape of the four we deal with now, the rest being integrated into these more complex structures. Out of the chaos of the Big Bang, not only were the more complex strcutures of matter and energy created, but the various forces that act upon that matter and energy were established, itself acting back upon these increasingly complex strcutures, to provide them even more with form and structure, and driving forward their complexity.

From simple atoms, molecules were formed, out of the formlessness, gravity acted to bring these molecules together in plasma and gas clouds. Out of these clouds, more order and structure was formed creating stars, planets and galaxies. I don't see order descending into chaos there I see the opposite. I see a tendency in our Universe for order and structure, DESPITE the high probability that you would expect to the opposite. But, it doesn't end there.

If we look at our planet, we see the same process. The probability that chaotic atoms would come together to form the molecules that form the basic amino acids that are the building blocks of life, is also highly improbable. Yet, again we see that it happened, despite the improbability. The likelihood that the amino acids would combine, and form life is improbable, and yet it happened. If we look at life itself, even simple plant life, rather than chaos out of order we see the exact opposite. How improbable is it that chaotic atoms of carbon dioxide, should be consumed by plants and through photosynthesis be tuned into energy. How improbable is it that chaotic atoms of nutrients in the soil, or the molecules of water should be trapped by plants, and transformed from such chaotic existence into the order and structure of complex cells? How unlikely is it that these cells should organise themselves into more complex structures to form leaves, stems, flowers, seeds, and so on? Once again, what we see is not a tendency for chaos out of order, but order and structure being formed out of chaos.

The most complete expression of that is the establishment of intelligent life itself i.e. us. How improbable is it that the various amino acids, should come together to form cellular life, that through a process of natural selection, which is itself an expression of a tendency towards order and strcuture out of chaos, should end up with the amazingly complex strcuture, which is the human being? What I find interesting from a philosophical perspective is what this signifies. Scientists never tire of reminding us that we are all stardust. All of the elements that go to make up our material existence, were created in the stars. But, in fact, what human beings signify in becoming self-aware – including the self awareness that all we are is that stardust – is the Universe itself becoming self aware. I don't mean that in some kind of New Age mystical sense.

If we consider our own self-awareness, we wouldn't say, for example, that our leg was self aware. Yet our leg is part of us. Animals are not self aware, and so it is obvious that it is not just the brain that is elf aware either. It can only be some part of the human brain that is self enables us to be self aware. Yet, without our legs, arms, heart, lungs and so on we could not exist, for that part of the brain to provide us with that self awareness. In the same way, humans as just some infinitessimally small part of the Universe, by becoming self aware represent that Universe becoming self aware, precisely because without it, we could not exist, and we are an inextricable part of it.

The obvious illustration of that, is the way in which human beings are able to consciously change matter, and energy, thereby changing the nature of reality and of the Universe. It might be highly improbable for sand to spontaenously organise itself into the shape of a sandcastle, but matter that has formed itself into a human being has no difficulty whatsoever in shaping that sand to be a sandcastle, or other matter to form telescopes, space shuttles or whatever we develop the technology to construct. Once again, the chaos that was transformed into order to form human beings, is once again via a feedback loop raised up into a means for constructing even more order, even more structure, even more complexity.

But, as Brian pointed out, humans have done this in a fantastically small period of time considering the age of the Universe already. As he pointed out, 2,500 years ago, humans still thought the Sun was a God. But, in fact, most of man's achievements in bringing order and structure to the Universe have not been the work of the 200,000 years Mdoern man has been about, or the 5,000 years since the dawn of civilisation. They are in fact, the product of man's achievement over more or less the last 250 years. As Marx writes in the Communist Manifesto,

“The bourgeoisie has disclosed how it came to pass that the brutal display of vigour in the Middle Ages, which reactionaries so much admire, found its fitting complement in the most slothful indolence. It has been the first to show what man’s activity can bring about. It has accomplished wonders far surpassing Egyptian pyramids, Roman aqueducts, and Gothic cathedrals; it has conducted expeditions that put in the shade all former Exoduses of nations and crusades.”

My question, would then be, in a Universe, which, despite all of the improbabilities, has spontaneously created the order of stars, galaxies and planets out of the chaos of a formless soup of fundamental particles, that has grouped spontaneously generated the conditions on at least some of those planets for life to be established, and for intelligent life to be established, that has seen in the space of just 250 years, the most complex to date product of this process of creating order out of chaos – Man – begin to harness the forces of Nature, including the understanding of how the Universe was created, and of what it is composed, and how it works, who would bet against such a Universe continuing to find means by which of creating order out of chaos? If Man has created the level of order out of chaos we see in such a small timescale, who can say what further advances Man, or some other intelligent life form might be capable of in the millenia to come? Already, Man is moving from his own self-awareness to develop intelligence and self-awareness in non-organic forms i.e. in computers and robots. I don't think we should confine the Universe to its ultimate heat death just yet.

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