Skip to main content

Quantum Reality - Jim Baggott ****

At one time it was popular amongst some physicists to be extremely critical of philosophy. For example, in their book The Grand Design, Stephen Hawking and Leonard Mlodinow aimed to answer a series of what have long been seen as philosophical (such as 'Why are we here?', 'What is the nature of reality?' and 'Did the universe need a creator?') by ignoring philosophy and taking a purely scientific viewpoint. Philosophy, those authors assured us, like religion, was now dead.

I'm afraid Hawking and Mlodinow failed to convince, which is why it's perfectly reasonable for Jim Baggott to come up with a book on a physics topic, what 'lies beneath' quantum theory, and, along the way, to spend a fair amount of the book introducing philosophical concepts put across by philosophers.

Quantum physics is arguably unique amongst the hard sciences in having a range of interpretations that run from 'We don't know what is happening and never will' (typified in the response 'Shut up and calculate') all the way through to detailed interpretations which do away with some of the problems we face in the traditional approach, at the cost of introducing a whole new series of problems, such as the extravagant requirement for the 'many worlds' interpretation that there are vast numbers of parallel universes.

Baggott is a master of taking complex concepts and making them surprisingly accessible. For much of what's difficult and confusing about quantum physics interpretations he succeeds in doing this admirably. For example, he gives the first explanation I've ever read of one of the more philosophical interpretations of quantum theory, quantum Bayesianism, or QBism, which I found in the slightest bit comprehensible. For me, the book was worth reading for that alone.

I also found that Baggott gave fascinating details on the philosophical side I was unaware of, from the philosophers of science like Karl Popper to the hardcore philosophers behind some of the concepts required to understand quantum interpretations, such as Immanuel Kant. Personally, I've never been hugely bothered about philosophy, but it is simply impossible to really dig into these interpretations without taking philosophy on board, so this was great.

What I thought was a little less accessible was the descriptions of quantum phenomena. These were illustrated with little pictograms which I found hard to follow, particularly as the print was so small I couldn't read the text. Sometimes, in the effort to avoid getting too technical - for example in describing what was meant by an operator and an expectation value - there was insufficient detail to get your head around the concept. And I did find a metaphor repeatedly used involving an island of metaphysical reality, the sea of representation, the ship of science and the land of empirical reality (with Scylla and Charybdis thrown in, which I can't really remember what they were intended to be) more confusing than helpful. But these are small details that didn't prevent the book being fascinating.

Throughout, Baggott is approachable and often has a wonderful turn of phrase (I loved, for example, the description of Paul Feyerabend as 'a Loki among philosophers of science'). In the end, a lot of the tension in the book is between realist interpretations ('There is something underneath that we could in principle uncover') and anti-realist ('It is impossible to ever discover a reality beneath - shut up and calculate'). As someone who feels more comfortable in the anti-realist camp, I couldn't agree with Baggott's assessment that realist interpretations are 'more palatable' - I think it's useful to read Philip Ball's Beyond Weird as well for a contrast - but I very much enjoyed getting a better background on the different possibilities.

Using these links earns us commission at no cost to you
Review by Brian Clegg


Popular posts from this blog

On the Fringe - Michael Gordin *****

This little book is a pleasant surprise. That word 'little', by the way, is not intended as an insult, but a compliment. Kudos to OUP for realising that a book doesn't have to be three inches thick to be interesting. It's just 101 pages before you get to the notes - and that's plenty. The topic is fringe science or pseudoscience: it could be heavy going in a condensed form, but in fact Michael Gordin keeps the tone light and readable. In some ways, the most interesting bit is when Gordin plunges into just what pseudoscience actually is. As he points out, there are elements of subjectivity to this. For example, some would say that string theory is pseudoscience, even though many real scientists have dedicated their careers to it. Gordin also points out that, outside of denial (more on this a moment), many supporters of what most of us label pseudoscience do use the scientific method and see themselves as doing actual science. Gordin breaks pseudoscience down into a n

A (Very) Short History of Life on Earth - Henry Gee *****

In writing this book, Henry Gee had a lot to live up to. His earlier title  The Accidental Species was a superbly readable and fascinating description of the evolutionary process leading to Homo sapiens . It seemed hard to beat - but he has succeeded with what is inevitably going to be described as a tour-de-force. As is promised on the cover, we are taken through nearly 4.6 billion years of life on Earth (actually rather more, as I'll cover below). It's a mark of Gee's skill that what could have ended up feeling like an interminable list of different organisms comes across instead as something of a pager turner. This is helped by the structuring - within those promised twelve chapters everything is divided up into handy bite-sized chunks. And although there certainly are very many species mentioned as we pass through the years, rather than feeling overwhelming, Gee's friendly prose and careful timing made the approach come across as natural and organic.  There was a w

Michael D. Gordin - Four Way Interview

Michael D. Gordin is a historian of modern science and a professor at Princeton University, with particular interests in the physical sciences and in science in Russia and the Soviet Union. He is the author of six books, ranging from the periodic table to early nuclear weapons to the history of scientific languages. His most recent book is On the Fringe: Where Science Meets Pseudoscience (Oxford University Press). Why history of science? The history of science grabbed me long before I knew that there were actual historians of science out there. I entered college committed to becoming a physicist, drawn in by the deep intellectual puzzles of entropy, quantum theory, and relativity. When I started taking courses, I came to understand that what really interested me about those puzzles were not so much their solutions — still replete with paradoxes — but rather the rich debates and even the dead-ends that scientists had taken to trying to resolve them. At first, I thought this fell under