I don’t think anyone would confuse this with an easy read. Alvin Toffler’s Forward ends by saying that while this book is challenging, it rewards the attentive reader. I’m not convinced attention is the only thing required here. The physics discussed requires more than the standard basic overview knowledge that books for a lay audience expect. Parts of this were simply too hard for me. That said, this is an incredibly interesting book – it sits (and quite consciously too) where philosophy meets physics.
You could almost get away with reading the introduction and the conclusion to this one – I’ve re-read both to write this review. In fact, if you don’t want to feel overcome with examples from physics, and that giddy feeling of acrophobia that comes from reading paragraphs like this (chosen at random from the middle of the book):
“Up to now it has been assumed that the “control substances” (A, B, D, and E) are uniformly distributed throughout the reaction system. If this simplification is abandoned, additional phenomena can occur. For example, the system takes on a “natural size,” which is a function of the parameters describing it. In this way the system determines its own intrinsic size—that is, it determines the region that is spatially structured or crossed by periodic concentration waves.”
My suggestion is that you would acquire the main ideas of this book that are most relevant to ‘the rest of us’ from reading the introduction and conclusion. All the same, here’s the McCandless version of what I got out of this book.
For Plato, there was something deeply wrong with the world. Everything is change and decay – but clearly no god worthy of the name would make such a world. The world ought to reflect the highest realisation of pure reason, since, surely, pure reason is as close to the best definition of ‘godly nature’ as we can think of. And so, Plato decided that the world we see around us can’t be the really real world – but rather a poor copy of god’s perfect ‘world of forms’. In the world of forms everything is eternal, perfect, change is impossible, laws are laws (not to be broken) and everything remains the same for all eternity.
Much of science has been looking for something approximating this world of forms ever since. Something that has been particularly true of mathematics and physics. And with Newton, people thought that they had come pretty close to finding just such a world. In Newton’s world, if you knew the initial conditions of all of the atoms in the universe (their initial positions and their velocities) then, the story went, in a mechanical universe you could know every damn thing would happen from that moment forward. It would just require a big enough computer; all the rest would be solving differential equations. What looks to us like accidents and free will, would be, to this all-seeing eye, necessity. It would all be a matter of us just not having enough precision in measuring the initial conditions ad computing power to run the universe backwards and forwards.
For Einstein, the universe was a little different. It had four dimensions, one of which was time, but time was much the same as the other three. We might not be able to move backwards and forwards in time in the way we clearly can in space, but there was nothing in the equations to make time any different to moving forwards and backwards or up and down in space. The fact we don’t see time in that way is just one of those strange prejudices of humanity, a myth we can’t seem to think outside of, but also one that stops us from seeing the true nature of the universe. They quote Einstein himself on this, “For us convinced physicists the distinction between past, present and future is an illusion, although a persistent one.”
Don’t get me wrong, I’m 57, I would love it if Einstein could be proven right on this one. If there was ever a time when moving seamlessly backward in time at will would be a rather pleasant way to spend a weekend, this would be it. A lot of this book takes seriously the fact that moving backwards in time simply isn’t possible.
A long time ago I read A Brief History of Time. I was working as an archivist at the time and a guy I didn’t really know asked me what I thought of it. I said I felt Hawking had placed a bit too much emphasis on Heisenberg’s uncertainty principle. There was a pause, and then he changed the subject. It was only years later that I found out most people who had bought the book hadn’t actually read it.
There is no nice or kind way to say this. This book is harder to read than Hawking’s. But I think it is more valuable too. Both of them explain the idea of the arrow of time and how it is based on the fact that overcoming the second law of thermodynamics really isn’t an option. The second law of thermodynamics is the law of entropy, the idea that things fall apart.
Let’s say you drop a glass and it smashes on the ground. This isn’t an insanely difficult thing to do and requires remarkably little energy. But let’s say we then want to move backwards in time – then the glass will have to spring back up onto the table reforming as it does so. While the energy needed to smash the glass in the first place is hardly any at all – the energy needed for it to spring back together again is infinite. That is, not a lot of energy, but infinite energy. Dropping a glass simply isn’t a reversible experiment. Entropy, the march of the universe towards increasing states of disorder, is impossible to reverse. And this is the most confirmed law in science because proving it wrong would prove such a boon for us humans. The second law is the only thing standing between us and immortality. It is the only thing standing between us and perpetual motion machines. Finding reasons why we would want to figure out how to break the second law isn’t the thing that is lacking – the second law is (in the words of Billy Bragg about the law of gravity) ‘very, very strict’.
But our world doesn’t merely fall apart – even if WE increasingly do with time. Systems not only become more disordered, but when they are pushed beyond equilibrium they often display emergent order. This is chaos theory – that while it becomes impossible to predict the precise future state of a system, particularly in systems that are pushed into chaos and so are highly dependent upon the tiniest of fluctuations (the fabled ‘butterfly effect’) – order also spontaneously emerges in such systems. Such systems evolve. Evolution becomes for our time what the clockwork universe was for Newton’s. Like the breaking of a wine glass, evolution is non-reversible and non-repeatable in exactly the same way as before. We get a complex world, one that is constantly on a knife’s edge. But just because such a world cannot be replayed so as to produce the exact same result this no way means that we live in a world without laws.
The difference is that order comes at a price. And that price is the determinism that seemed so tantalisingly close with Newtonian dynamics.
There are benefits to this as well as costs, however. In the case of society (a complex system if there ever was one) it means that individual actions are never truly without consequence – and this becomes increasingly the case as the system is pushed further and further out of equilibrium.
There are a few myths about science that this book plays with in particular. One is the idea that we essentially know all there is to know about the physics of ‘our scale’ of the universe – but that the physics of the very big or the very small is what still eludes us. And to counter this idea, all of their examples of non-reversible physical processes in this book are from our scale.
The other myth is that science is somehow more objective and less socially determined than the arts. The standard story we tell ourselves is that while someone would have eventually come up with Newton’s three laws of motion if Newton hadn’t ever gotten around to it, if Bach had never lived, then so much for the Goldberg Variations. The authors point out that this isn’t nearly as obvious as is often claimed. Not that we definitely would have ended up with the Goldberg Variations, but rather that discoveries in science aren’t nearly as objectively necessary as we like to think them, that they too share something of the creativity of Bach. Sometimes scientific discoveries can feel like a missing piece that simply demands to be discovered, but often scientific discoveries emerge out of their time. The authors speak of many ideas that never quite took off because society simply wasn’t ready for them, and the opposite is clearly also the case – where scientists haven’t started looking for answers until the question began to made sense to ask. And that is generally due to other social motivations. As the authors say of their own research interests, “how can we consider as accidental that the rediscovery of time in physics is occurring at a time of extreme acceleration in human history?”
This really is a stunningly interesting book – but some of it is so hard that really, no amount of concentration is enough. The authors do their best, but what they are talking about is damn hard and perhaps can’t really be made any easier. Still, the implications of their ideas are well worth thinking over, and through, and then over again.