1 of 1 people found the following review helpful
Verified Purchase(What is this?)
This review is from: The End of Time. The Next Revolution in Our Understanding of the Universe (Hardcover)
Julian Barbour, a well-known maverick at conferences, has managed to present his unorthodox views in a balanced and accessible way in this popular treatment. His singular vision ties together the various themes in a startling manner. The theory therein is exciting, disturbing, and invigorating.
Somehow a rather complex set of ideas incorporating the canonical approach to quantum gravity, the many worlds interpretation of quantum mechanics, and Barbour's novel approach regarding configuration space are presented at a level anyone bothered to put the time in (ho ho) can understand. Generally, Barbour is good at laying out ideas in a simple manner, although he does occasionally transition from carefully explaining everything to quickly reeling off some technical sentence or other, albeit only in a minority of cases. He writes equations out in words, with some loss of technical generality, on the other hand. My main minor criticism of the book is his description of the wavefunction as three coloured 'mists'. Despite my training in QM, I got lost sometimes when trying to remember whether blue represented probability or position and so on.
I think the main reason the book works is because Barbour's theories are themselves usually only describable in qualitative terms anyway, since quite preliminary. I've often thought cutting edge ideas are often easier to explain than well-established ones, since often they only exist in qualitative form. And Barbour has a vision, a breathtaking vision, one that incorporates many themes that are now (2012) even 'hotter' then they were back in 1999, which I think is the original publication date. Barbour's approach to QG is fascinating, even if it should prove false.
One further minor quibble, however, is that the book is called the end of TIME, and Barbour's theory is presented as a theory of time (i.e. there isn't any 'flow,' etc.), yet in reality it is an anti-realist position with regard to MOTION and/or real 'becoming,' NOT 'time' as such. The further independent argument required - that time is reducible to change, motion, etc. - even if plausible, is nowhere satisfactorily provided. The nearest Babrour comes to providing such, in my view, is when he mentions a critique of Ashtekar's views. (It may be objected that Barbour's positive arguments for a 'Machian' approach incorporate a certain denial of absolute and/or real time, but this requires an argument. Since distinctions such as denying A-series, B-series, or C-series time are not addressed, for example).
Incidentally, where Barbour contrasts his MWI with other historical Everettian's, including Everett, an update would be interesting, since the field has moved on so much since 1999, perhaps partly inspired by Barbour's book.
All in all, this is an accessible and brilliant book, containing one of the most interesting unified views on nature, physics and time ever. If you enjoyed Deutsch's Fabric of Reality from the late 90s, you'll probably enjoy this book too. Barbour is careful, perhaps more so than Deutsch, to point out his ideas are unorthodox, in terms of the 'sociology' of physics. However, much as in the case of Deutsch, a sizeable and growing minority of physicists are developing ideas that resemble many of those contained in this book.
I should note that I find Barbour's conception of 'Nows' or 'instants' physically incoherent, but that it took me a long time to work around his many brilliant and subtle arguments contained herein.
Sort: Oldest first | Newest first
Showing 1-1 of 1 posts in this discussion
Initial post: 26 May 2012 11:28:52 BDT
Just wanted to add that since writing this review I've been convinced by some comments of Simon Saunders that I was too hasty in my judgement found in the last sentence of the review. Basically, it relates to some worries about 4D covariant QFT - however, I'm now convinced I was too hasty and hadn't understood Barbour's motivation. Barbour is looking to some as yet unspecified canonical approach to QG, and has very interesting ideas re what he calls the 'deep structure of GR'. I now recant the final sentence of my review.
‹ Previous 1 Next ›