Why do we exist?
Why this particular set of laws and not some other?
This book is not for the fainthearted. At times, it stretches your credulity and fills you with existential doubt about the world around you. This begins right away in Chapter 1 which boldly contends that the answer to life, the universe and everything is not, in fact, 42. Then, while you are still reeling from this, in Chapter 2, it claims that Pythagoras didn’t invent Pythagoras’s theorem. Is nothing sacred?! And don’t get me started on the part which says that it is possible that the Matrix is true. Abandon hope all ye who enter here: this way lies damnation.
This book is a fierce combination of the utterly fascinating and utterly tedious. Almost page by page, I oscillated between being totally absorbed and totally bored. It kicks off with a history of the development of science and its links with religion to demonstrate that science developed as people began to notice patterns, and then laws, in nature. They throw up intriguing questions like “Do physical laws have equivalents for people? animals? worms?” and “Do we have free will, and, if so, are we governed by laws of nature in how we deploy it?”. Apparently there are too many variables to be able to predict human behaviour, but it is possible that, as you sit sipping your cappuccino and reading this blog, you have not made a free decision about what to do with your coffee break, and instead it is in fact the will of Science that you read it. Given that we shouldn’t go against the laws of nature, I suggest you read this blog every day, just to be safe.
They then go on to say that we fundamentally don’t understand anything, and that what we think is happening in the world is based on the models we create of the world. This is called ‘model-dependent realism’ – a phrase you should throw into conversation the next time you are trying to escape a bore at a party (unless you are unlucky enough for the bore to also be a physicist).
So we then go on to think about the models we have used to understand the world and how we have moved from Newton’s apple-based version of gravity to the baffling models of quantum mechanics.
There are three things you need to know about quantum mechanics:
- The importance of waves. Apparently, electrons behave like water waves and particles at the same time. This was, allegedly, a very exciting discovery, and is very important to quantumness (different from Mr Tumnus).
- The Werner Heisenberg Uncertainty principle: which basically means that you can’t accurately measure the speed and position of a particle at the same time. You have to choose which one you care about most and accept that the other measurement will be a bit off.
- You can never really accurately predict the outcome of physical processes because they are not predetermined. Apparently this used to really upset Einstein (he clearly needed to get out more). So essentially quantum theories are all about guessing the probabilities of things happening given that nature is essentially random.
I can’t really remember the impact all of this has on anything, but it certainly all sounds very impressive. There really was a lot of talk of waves in this book. And lots of wavy pictures. If, like me, your brain is beginning to ache, don’t feel bad. Apparently, Nobel prize winning physicist Richard Feynman once wrote “I think I can safely say that nobody understands quantum mechanics” which begs the question of why they are writing a popular science book about it if it isn’t properly understood by scientists yet. But, who am I to question?
What will really make your brain ache: Feynman’s theories on particles travelling
If you fire a particle from point A and it lands at B, Newton (and common sense) would have you believe that the particle would take a straight line route to get there. Feynman, for some reason, believed that, instead, the particle takes every possible route to get there (including via your shepherd’s pie). Simultaneously. The poor particles must be exhausted. And sticky. This in some way relates to something called Planck’s constant which I don’t understand. Happily for us though, this rule only applies to things that are particle sized, so if someone throws a football at your head, you should still duck.
This means that history becomes pretty meaningless as there is no way of knowing the history of any particle because it had so many different histories and, similarly, you can’t tell the history of a universe because it is made up of particles all of which have simultaneously been everywhere and done everything. As a student of history, I find this idea deeply upsetting. Feynman also believed that observing a system alters its course. This sounds suspiciously like believing that a watched pot never boils, or that waiting in for a call means the phone won’t ring, to me.
This is all very well, but 80 pages in I am still not clear on the ‘so what’ of all of this. I have to keep
reminding myself that practical application is not the point: this is purely about the search for knowledge for its own sake. It just feels like a lot of work to understand it all when they haven’t even figured out all of the answers yet. I also suspect that despite the brain-ache, a gin is not going to aid comprehension of this book.
The book then turns to considering the 4 known forces of nature:
- weak nuclear force (which causes radiation)
- strong nuclear force (which holds atoms together)
And we have a long diversion in which previous theories from Newton, Einstein and Maxwell about how all of these worked were debunked. These are now being replaced by quantum theories (based on waves and uncertainty). By the time we got to virtual particles (which sound even worse than imaginary numbers) my eyes were rolling in my head.
But then it got interesting again as we turned to how the universe was created (they bluffed quite hard but I still don’t think they know) and about how they think there are lots of dimensions, some of which are mysteriously curled up, while others aren’t. This was again interesting but not brilliantly explained (or perhaps I wasn’t paying full attention) but there was a good bit about the universe having started as a series of bubble universes, some of which popped. What they didn’t come close to answering though is the question that still torments my brain – if the universe started as a dot and is expanding outwards, what is the universe in???
Perhaps that will be the topic of their next book.
For those of you that made it this far, here is a physics joke from E as a reward:
A photon checks into a hotel and the porter asks if it has any luggage. “No,” the photon replies “I’m travelling light!”