Skip to main content

Quantum Space: Jim Baggott *****

There's no doubt that Jim Baggott is one of the best popular science writers currently active. He specialises in taking really difficult topics and giving a more in-depth look at them than most of his peers. The majority of the time he achieves with a fluid writing style that remains easily readable, though inevitably there are some aspects that are difficult for the readers to get their heads around - and this is certainly true of his latest title Quantum Space, which takes on loop quantum gravity.

As Baggott points out, you could easily think that string theory was the only game in town when it comes to the ultimate challenge in physics, finding a way to unify the currently incompatible general theory of relativity and quantum theory. Between them, these two behemoths of twentieth century physics underlie the vast bulk of physics very well - but they simply can't be put together. String theory (and its big brother M-theory, which as Baggott points out, is not actually a theory at all but simply a conjecture) has had much written about it. But the main alternative theory, loop quantum gravity has had far less coverage. As I mentioned in another review (and Baggott also picks this up), in one whole book on gravity, loop quantum gravity is only mentioning in an endnote. Yet in many ways, loop quantum gravity has a lot more going for it than string theory.

One major strand of Quantum Space is a biography of two key players in the field - Lee Smolin and Carlo Rovelli, both good writers for the general public in their own right, but neither has been able to come close to what Baggott does in trying to make the ideas of loop quantum gravity accessible at a deeper level than a summary, hand-waving description. It’s also the first complete and approachable account I’ve seen of how both approaches to a quantum theory of gravity were derived. The only downside of the way it's structured is that I think if you’re going to be comfortable with the level of detail Baggott gives, you probably don’t need the first 100 pages or so giving background on quantum theory and general relativity.

My only real concern apart from that unnecessary opening material, which makes the book a little too long for my tastes, is that there could have been more unpacking of how loop quantum gravity represents reality - the jump from the introduction of spin networks to anything resembling a theory that can be applied to a real world where things happen is overwhelming. I had to resort to the much valued advice of one of my supervisors at university who said 'Don't worry if it doesn't all make sense, just keep on with it and hopefully it will all come together.' It almost all did all come together, but I was left with a nagging doubt that I couldn't really grasp the foundation of the whole idea.

As well as coming out of reading this book with significantly more respect for Rovelli (whose popular science writing I find flowery and overrated), I feel that Baggott has done a huge favour for anyone who really wants to understand modern theoretical physics, giving a much better understanding of this fascinating attempt to deal with a central requirement to explain the workings of our universe. It's a triumph.
Hardback:  

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

Labels

Labels:

Comments

Post a Comment

Popular posts from this blog

The Decline and Fall of the Human Empire - Henry Gee ****

In his last book, Henry Gee impressed with his A (Very) Short History of Life on Earth - this time he zooms in on one very specific aspect of life on Earth - humans - and gives us not just a history, but a prediction of the future - our extinction. The book starts with an entertaining prologue, to an extent bemoaning our obsession with dinosaurs, a story that leads, inexorably towards extinction. This is a fate, Gee points out, that will occur for every species, including our own. We then cover three potential stages of the rise and fall of humanity (the book's title is purposely modelled on Gibbon) - Rise, Fall and Escape. Gee's speciality is palaeontology and in the first section he takes us back to explore as much as we can know from the extremely patchy fossil record of the origins of the human family, the genus Homo and the eventual dominance of Homo sapiens , pushing out any remaining members of other closely related species. As we move onto the Fall section, Gee gives ...
Post a Comment
Read more

Pagans (SF) - James Alistair Henry *****

There's a fascinating sub-genre of science fiction known as alternate history. The idea is that at some point in the past, history diverged from reality, resulting in a different present. Perhaps the most acclaimed of these books is Kingsley Amis's The Alteration , set in a modern England where there had not been a reformation - but James Alistair Henry arguably does even better by giving us a present where Britain is a third world country, still divided between Celts in the west and Saxons in the East. Neither the Normans nor Christianity have any significant impact. In itself this is a clever idea, but what makes it absolutely excellent is mixing in a police procedural murder mystery, where the investigation is being undertaken by a Celtic DI, Drustan, who has to work in London alongside Aedith, a Saxon reeve of equivalent rank, who also happens to be daughter of the Earl of Mercia. While you could argue about a few historical aspects, it's effectively done and has a plot...
Post a Comment
Read more

Amazing Worlds of Science Fiction and Science Fact: Keith Cooper ****

There's something appealing (for a reader like me) about a book that brings together science fiction and science fact. I had assumed that the 'Amazing Worlds' part of the title suggested a general overview of the interaction between the two, but Keith Cooper is being literal. This is an examination of exoplanets (planets that orbit a different star to the Sun) as pictured in science fiction and in our best current science, bearing in mind this is a field that is still in the early phases of development. It becomes obvious early on that Cooper, who is a science journalist in his day job, knows his stuff on the fiction side as well as the current science. Of course he brings in the well-known TV and movie tropes (we get a huge amount on Star Trek ), not to mention the likes of Dune, but his coverage of written science fiction goes into much wider picture. He also has consulted some well-known contemporary SF writers such as Alastair Reynolds and Paul McAuley, not just scient...
Post a Comment
Read more