193 of 195 people found the following review helpful
A mathematical origin to the universe?,
This review is from: Cycles of Time: An Extraordinary New View of the Universe (Hardcover)
Many who wish to buy this book will be familiar with the other works of Professor Roger Penrose (such as The Road to Reality). Some will be curious to learn about a new theory of the origin of the Universe. This book presents a radical new idea which Penrose has been developing in the past few years on the Big Bang: essentially the idea is that there was a pre-Big Bang era and there will be a post-Big Crunch era too.
So one could review both the book and the idea itself. Firstly some will worry about the level of mathematics presented in this book. In the main chapters there are equations such as S = k log V - Boltzmann's Equation. If you are not comfortable with this, then maybe you will not get the most from the book. However if you are comfortable with this and similar physics equations and numbers then the first section of the book is readable. Of course there are plenty of diagrams too. There is some hard maths however and this has been relegated to the Appendix (30 pages). This maths is very advanced and another of Penrose's technical books (Penrose and Rindler Volume 2) would be needed to understand it fully - so that is only for the experts. Given that the reader wont be learning this material in the present book it shows that there is some more complex machinery behind the scenes needed to comprehend the full idea.
In the first section the book returns to an old concern of Penrose namely the entropy present in the early universe: less than today - but why so much less? The chapter then focusses in on the Big Bang described using "Conformal Diagrams". The key on page 115 is important for reading these diagrams.
Part 3 introduces the new idea called Conformal Cyclic Cosmology (CCC). Here we learn something about the idea that the Big Bang is merely a transition in the longer history of the universe. To get the most out of the mathematics in this section one needs to understand the idea of the conformal metrics introduced. Fortunately there are no calculations about it in the main text, but the idea needs to be understood. In order to develop the CCC hypothesis Penrose then needs to consider various physics issues: entropy, black hole information loss, the presence of mass in elementary particles. A novel use of other work in these areas provides for an interesting basis for the CCC hypothesis as we also study the far future of the Universe. Finally we close with some observational details from the Cosmic Background Data being gathered by satellites. So CCC is a physically testable theory!
If you are interested in another theory being presented at the forefront of Cosmology and Physics then this is for you. Also it provides another view of Penrose's approach to these subjects which is different from the mainstream. But beware that some of the mathematical ideas (of conformal infinity) go quite deep indeed - easily the subject of another book if this idea is successful!
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Initial post: 7 Oct 2010 16:32:56 BDT
Dr Simpson's review shows that Professor Penrose's book is completely beyond my comprehension. However, I have just read Stephen Hawking/Leonard Mlodinow's book, The Grand Design (Sept. 2010), three or four times in a couple of weeks. Although I take a very negative view of Hawking's philosophizing in his book - Hawking proclaims, self-contradictorily, that 'philosophy is dead' (p.5) - and although one can gain only a very limited cosmological understanding of what Hawking is saying because his explanations are so 'simplified', I would be very interested if Dr Simpson (or some other equally scientifically qualified reviewer) would be able to tell me if Penrose's book agrees with Hawking that string-theory/multiverse-theory/M-theory is the final explanation of The Grand Design, so that these theories are indeed 'New Answers to the Ultimate Questions of Life' (Hawking's subtitle). For Hawking, his views are not only 'new answers' but the long-searched-for final answers. Would Penrose agree with Hawking's replies to Hawking's own questions: [All] the universe[s] came about spontaneously, without any cause other than ineluctable laws of nature that preceded (when there was as yet nothing) but nevertheless determined the emergence and shape of something from nothing; there is no such thing as free will (or miracles), so human nature is wholly programmed and pre-determined down to its tiniest actions (Hawking p. 32), and the 'laws of nature' (which preceded the existence of nature) could not have been (at least in this universe) other than they are.
How does Penrose's theory of Conformal Cyclic Cosmology relate to Hawking's M-theory?
In reply to an earlier post on 7 Oct 2010 17:05:19 BDT
Last edited by the author on 7 Oct 2010 17:27:27 BDT
Dr. Roy Simpson says:
The comment by Trini raises questions for a larger discussion, than just a review of this book. A short answer is that Penrose and Hawking's books were published at around the same time and do not directly quote each other.
In this book Penrose refers to a couple of String based ideas similar to CCC, but Penrose is not a strong supporter of String Theory, and for that reason prefers his own approach described here. In his earlier book (The Road to Reality 2004) Penrose presents various reasons for not accepting String Theory in its current form. As for any complete reconciliation of Penrose and Hawking's views - that is yet to come.
In reply to an earlier post on 11 Oct 2010 20:40:13 BDT
Last edited by the author on 11 Oct 2010 20:59:43 BDT
Dr Simpson, Thank you for your comments.
I have been reading around this question of the extent of the support for Hawking/Mlodinow's book, and have found the amazon.com (USA) reviews to be very informative. I have been particularly impressed by the discussion triggered by the review (2-star) of The Grand Design by Mike Birman on 8th September. As of 11th October, '304 of 393' readers found Birman's review helpful, and it has elicited 212 comments. Of great interest is Birman's own very recent comment (somewhere about the 210th comment) analysing the reviews of all the 5-star reviewers, which amount almost hysterically to little (or nothing) less than the apotheosis of Hawking.
In reply to an earlier post on 2 Jan 2011 09:56:34 GMT
Dr. C. Jeynes says:
I think reviewing reviews can be interesting and helpful, especially in a deep subject like this. I liked Penrose's book (see my review) although I am not convinced by it. But he definitely does not agree with Hawking, taking a diametrically opposite position!
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