Skip to main content

The Biggest Ideas in the Universe: Space, Time and Motion - Sean Carroll *****

In the brilliant Yes Minister/Yes Prime Minister TV series, an idea would be described as bold or brave it was stupid or career wrecking. In The Biggest Ideas in the Universe, Sean Carroll has done something extremely bold and brave. But - for the right audience (and we'll come back to that) - it is absolutely brilliant. A quick aside about the unwieldy title: this is the first entry in the 'Biggest Ideas' trilogy with two more to follow.

There are two broad ways to write about physics. You can take the popular science approach which is descriptive, gives context and, if done well, makes it possible to a good idea of what the science is about without bumping against the maths. Or you can write a textbook, which builds on a foundation of heavy duty mathematics. This will describe what physics is really about, but will be impenetrable to anyone without an appropriate degree. (And often exceedingly dull too.) Carroll has built a bridge between the two - something I thought was impossible until now.

Famously, Stephen Hawking was told that the audience for a book halved with every equation that was included. If this is really true, Carroll has a problem, because his book contains plenty of them. Starting simply with conservation and introducing the first equation in the definition of momentum, Carroll builds surprisingly rapidly. Not only does he approach change and dynamics using conventional analysis approaches, he also introduces Hamiltonians and Lagrangians (and, of course, partial differentials) when you are less than a third of the way through the book. By the end we've got both the special and general theories of relativity under our belt and have dealt with matrices, tensors and more.

This is astonishing - Carroll doesn't just throw in equations and loosely explain them, he gives quite detailed descriptions of where they've come from and how they are used. What we don't get, which a textbook would do, is any attempt to solve these equations or expect the reader to do anything too strenuous with them, but the amount of detail is remarkable.

Does it all work? No - almost inevitably. I have seen, for example, more approachable descriptions of the principle of least action, starting with the Baywatch Principle and least time, rather than plunging straight into least action. Yet, for the right audience (and we're nearly there), it is rarely the case that the reader is left bewildered. Carroll builds everything impressively in a way that is quite different from anything I've ever seen before.

So, the audience thing. Carroll says about equations 'they are not that scary.' He tells us he dreams of a world where 'as kids are running around at a birthday party, one parent says "I don't see why anyone thinks there should be new particles near the electroweak scale," and another immediately replies "Then how in the world are you going to address the hierarchy problem?"' I'm sorry, Sean, but dream on. It's not going to happen. There are two big problems here for a truly general audience.

One is that I think Carroll totally underestimates the depth of many people's struggle with maths. It's not so much that equations are scary for those who say they don't like maths as that they repel readers without any information going into the brain. I don't think Carroll's beautiful build of the maths underlying physics will help such people at all. The other problem is that it would be possible to absorb everything in this book and you still wouldn't get the kind of conversation Carroll envisages - getting a better understanding of how physicists do their work will not allow you to go beyond what you've learned to pose those kind of questions.

A while ago I was listening to Mark Kermode and Simon Mayo's film podcast. They had asked for a simple physics explanation of multiverses. These aren't stupid people. Yet the point at which they wen't into 'This is too complicated, it's beyond me' was when the physicist said something like 'When you think of a quantum particle like an electron'. Their minds had already blanked out. Does anyone really think that such people, intelligent but not science-oriented, would ever come round to Carroll's way of thinking? 

I see the audience of this book as twofold. For people like me who have a decades old physics degree to get some nostalgic reminder of what I once knew, and for young people who are about to go to university to study physics to get a wonderful introduction to what lies beneath the mathematical slog they are about to go through and why it's all worthwhile. Any idea this will convert people who aren't already excited by physics, I'm afraid, is fantasy. But for the right people, this book is magnificent.

Hardback:   
Kindle 
Using these links earns us commission at no cost to you
Review by Brian Clegg - See all of Brian's online articles or subscribe to a weekly digest for free here

Comments

Popular posts from this blog

It's On You - Nick Chater and George Loewenstein *****

Going on the cover you might think this was a political polemic - and admittedly there's an element of that - but the reason it's so good is quite different. It shows how behavioural economics and social psychology have led us astray by putting the focus way too much on individuals. A particular target is the concept of nudges which (as described in Brainjacking ) have been hugely over-rated. But overall the key problem ties to another psychological concept: framing. Huge kudos to both Nick Chater and George Loewenstein - a behavioural scientist and an economics and psychology professor - for having the guts to take on the flaws in their own earlier work and that of colleagues, because they make clear just how limited and potentially dangerous is the belief that individuals changing their behaviour can solve large-scale problems. The main thesis of the book is that there are two ways to approach the major problems we face - an 'i-frame' where we focus on the individual ...

Introducing Artificial Intelligence – Henry Brighton & Howard Selina ****

It is almost impossible to rate these relentlessly hip books – they are pure marmite*. The huge  Introducing  … series (a vast range of books covering everything from Quantum Theory to Islam), previously known as …  for Beginners , puts across the message in a style that owes as much to Terry Gilliam and pop art as it does to popular science. Pretty well every page features large graphics with speech bubbles that are supposed to emphasise the point. Funnily,  Introducing Artificial Intelligence  is both a good and bad example of the series. Let’s get the bad bits out of the way first. The illustrators of these books are very variable, and I didn’t particularly like the pictures here. They did add something – the illustrations in these books always have a lot of information content, rather than being window dressing – but they seemed more detached from the text and rather lacking in the oomph the best versions have. The other real problem is that...

The Laws of Thought - Tom Griffiths *****

In giving us a history of attempts to explain our thinking abilities, Tom Griffiths demonstrates an excellent ability to pitch information just right for the informed general reader.  We begin with Aristotelian logic and the way Boole and others transformed it into a kind of arithmetic before a first introduction of computing and theories of language. Griffiths covers a surprising amount of ground - we don't just get, for instance, the obvious figures of Turing, von Neumann and Shannon, but the interaction between the computing pioneers and those concerned with trying to understand the way we think - for example in the work of Jerome Bruner, of whom I confess I'd never heard.  This would prove to be the case with a whole host of people who have made interesting contributions to the understanding of human thought processes. Sometimes their theories were contradictory - this isn't an easy field to successfully observe - but always they were interesting. But for me, at least, ...