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.

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

Comments

Popular posts from this blog

Who Invented the Computer? – Ian Watson

Ian Watson is the author of  The Universal Machine  and featured in a recent  Four Way Interview . Saturday June 23 2012 was the centenary of the birth of Alan Turing, the troubled genius who invented the modern computer. Why though do so few people recognize his name and his great achievements? In 1936 English mathematician Alan Turing, published a paper,  On Computable Numbers, with an application to the Entscheidungsproblem . This became the foundation of computing. In it Turing presented a theoretical machine that could solve any problem that could be described by instructions encoded on a paper tape. A Turing Machine could calculate square roots, whilst another might solve Sudoku puzzles. Turing demonstrated you could construct a single  Universal Machine  that could simulate any Turing Machine. One machine solving any problem for which a program could be written – sound familiar? He’d invented the computer. Then,  computers  were peop...

Ignorance: How it drives science – Stuart Firestein *****

This is a delightful little book that really gets you thinking. I stress the ‘little’ part not as a negative, but as a good thing. There is nothing worse than fat, bloated popular science books where the author feels they have to get 120,000 words to be taken seriously. This is the sort of book that can be read in a couple of hours – but you will get so much more out of it than one of those tedious doorstops. The premise underlying the book is in once sense extremely simple, yet is fundamental to an understanding of what science is and what scientists do. And it is an understanding that is totally at odds with the typical way science is portrayed both in university lectures and popular science books. As Stuart Firestein points out, what is important is not the facts, but rather the area of ignorance. The interesting part and the fundamental heart of science is not about what we know, but about what we don’t know and where we want to look next. Take this lovely quote: ‘Working ...

The Star Book – Peter Grego ****

This attractive landscape format book combines an excellent introduction to the stars and basic astronomy with a set of star maps, plus in depth looks at some of the stars featured, with a  bonus section on the solar system. Amazon says it’s a hardback, but in fact it’s a paperback with a rather ingenious cover – you can’t tell from the photo, but the words ‘The Star Book’ are punched through as a series of holes that show the white paper of the next page beneath. Like many astronomy/space books, the cover lacks shelf appeal because it is mostly black, but at least there is some original thought here. Unlike many books in this format which tend to concentrate on the pictures, there is a good deal of excellent text by Peter Grego, so there was no feeling that you were only getting the star maps and star ‘biographies’, something these days much more suited to an iPad or smartphone app. Instead, the opening 30 or so pages give a very good introduction that would be valuable to ...