Rating: 
Summary: Some good and some bad
Review: After taking a few evenings to complete this book I felt its over all quality a "B+".
Some of his speculations I felt a bit bizarre. I am not certain Einstein believed in "block time" which actually has nothing to evidence its reality except its convenience for phyicists.
For example block time was exampled by writing times, dates and events in a note book, each entry a block. Block time contends the past, present and infinte future are all equally layed out much like a landscape, but we poor humans only can be aware of our tiny slice in each frame of awareness,
So much for free will I suppose, oops!. And block time fails to also explain why we humans live in that fleeting second of consciousness, never able to move to past or future.I was confused and needed to reject the crazy idea that doomsday is not far away because our names ( persons ) are drawn at random by Nature from an urn ( figuratively). The conclsuion, because we are alive now , dooms day cannot be far away. I donot disagree doomsday may be not far with the bellicose and power mad politics of a nuclear age, but the urn analogy has nothing to do with it. Why would not the same urn concept have predicted mankind's demise 4,000 years ago yet we're still here. For all its silliness, and lack of detail and skepticisms, I thought this book's value in persuading laymen to think about the mystery of time and why we always live in the present. My view is that time is a psychological phenomenia and not physical.
Despite the big bang, the gas laws and the Humpy Dumpy example,
the equations of physics seem to work equally well in positive and negative time. The issue is we humans find the reversal of time without sense and reversing what we call causality. In any event this is a great book for Sci-Fi types and those that have wondered just how much science really knows or can know about the mystery of time.
A more complete book for the college educated is Times Arrow and Archimede's Point, Huw Price.
Rating:
Summary: A good, rather well-rounded expose on a difficult subject
Review: Almost, if not all, philosophical debates on the subject of 'time' center on a few questions which repeat themselves quite obsessively. The most frequent ones remain the simplest and the trickiest: What is time? Did it have a beginning? What makes it appear to flow? Why is there a directionality, or "arrow", of time, and can it ever be reversed, or stopped for that matter? Is time travel possible? And might the universe be older than we thought? These are but a few of those fascinating questions addressed in the book. Davies, writing with a nurtured and cultivated passion and characteristic wit, confronts the tough questions, those that still resist any explanation, including the weird relationship between physical time and our psychological perception of it. Several touchy subjects are tackled, such as the quantization of time, time travel and whether time really exists or is merely an illusion, besides giving straightforward descriptions of topics such as the theory of relativity, time dilation and Hawking's imaginary time. With his usual clarity and flair, Davies argues that time in the 20th century is Einstein's time and sets out on a thrilling discussion of why Einstein's can't be the last word on the subject. Davies concludes that despite decades of progress in unravelling the mysteries of time, the revolution begun by Einstein remains tantalizingly incomplete.
Rating: 
Summary: A very good book (and prophetic, too!)
Review: Author Paul Davies is probably best known for his "God and the new Physics" and "Mind of God". This book is a wide-ranging discussion of time in physics and cosmology (with an excursion into the psychology of subjective time).
Davies was one of the first to point-out the relationship between inflationary cosmology and the arrow-of-time problem, but he does not stress this point as effectively as B. Greene does in his more recent "The Fabric of the Cosmos": This book is a very good discussion of the problems of time, but I would recommend it more strongly if "The Fabric of the Cosmos" were not available.
Since this book covers cosmological problems, it must be considered somehow obsolete, as must be considered all books on cosmology written before the WMAP data became available. The WMAP satellite was launched in 2001, so you see that very few cosmology books are NOT somehow obsolete! (By the way, this only applies to books describing observations: theoretical books written more than 20 years ago can still be very useful.)
Anyway this is still a worthwhile read. Besides the many insights on the nature of time, this book is also somehow prophetic: the author predicted that a consistent cosmology would involve resurrecting Einstein's "cosmological constant". And this was written before the supernovae results first suggested that the universe is accelerating!
Still, a revised version with a better discussion of inflation and of the latest cosmological observations (WMAP, mostly) would be very useful. While Greene's "The Fabric of the Cosmos" is deeper and more up-to-date, I much prefer Davies' very lucid writing style.
Rating: 
Summary: Quantum mechanics, thermodynamics and time.
Review: I am a big fan of prof. Davies' books, but I found that this one had not the same high standard as his other books. Some chapters were boring and gave the impression that they were written purely to expand the volume of this work. But as always, he explains clearly and understandably his subject, like such important items as the opposite direction of time's arrow in thermodynamics (downhill) and in the Darwinist evolution(uphill), or the disappearance of time in quantum mechanics. Remarkably, one of the main themes of his more compelling and recommendable book 'The 5th Miracle' is already announced here: "Many scientists are adamant that the 'concretization' of quantum reality has nothing whatever to do with the mind, others maintain that the mystery of the 'collapse' (of the wave) and the mystery of consciousness are intimately bound up with each other." (p. 278) I prefer the books written by G. Whitrow about 'all sorts' of times.
Rating:
Summary: A wonderful book with clear explanations
Review: I never found such stimulating and satisfactory explanations about time in other books. This book is really wonderful, especially when the author expounds the case of the apparent paradox of twin's travel and her asymmetric aging at the end of the voyage or explains how to coordinate the concept of relative time with an "absolute" age of the universe or when he treats the problem of the "now" with the explanation (based on the Bayes'theorem of probability)of the future of the human race and so on. In conclusion, this book is very interesting and recommendable.
Rating: 
Summary: Painfully psuedoscience
Review: Paul Davies is a wonderful author, obviously well-versed in eastern mysticism; however, his understanding of physics leaves one wondering what his education gained him. From the outset in this book, we are riddled with flowering phrases that, although alluring to the curious mind and sense of magical wonder of the universe, are quite misleading in physical reality. Starting with his assertion that Einstein completely turned Newtonian mechanics on its head, he misleads the non-scientist down a path of dis-education and complete bewilderment. The theory of relativity reduces down to newtonian mechanics at slower velocities!! In this light, I fail to see any contradiction between the Einstein and Newton views of time. Unfortunately, many authors appeal to the general public on the grounds of either sensationalism or mysticism. The real physical universe is full of more wonder than any mystical experience could ever dream up! For a GOOD overview of physics that the layman can wrap their minds around, read just about anything by Richard Feynman...or start asking physics teachers and professors - you'll always find an enthusiastic physicist ready to untangle the knot of bewilderment and confusion left in the wake of such authors as Paul Davies!
Rating:
Summary: Not thorough enough
Review: This book provides an overview of topics related to the origin of time. These include Special and General Theories of Relativity, Quantum theory, discussions about the origins of space and time, superstrings, and others. In my opinion this book has too much prose and not enough depth. If you have a mathematical background, I would certainly recommend the Dover books by Einstein, Feynman, Heisenberg, Schroedinger, and others.
Rating:
Summary: Straightforward description of many topics about time.
Review: This is a book about the meaning of time, what it is, when it has started, how it flows and where to. If you ever wondered about the puzzles and paradoxes of time, if you ever wanted to learn more about what Einstein's relativity implies about time itself, this is a book you will not want to miss. Davies covers most of the questions about time; I found interesting how he explains the rather weird relationship between real time and our mental notion of it. The weirdness of bizarre possibilities should be enough to confuse anyone thinking about it for the first time; the way time relates to quantum physics, being sometimes even stranger to understand. Black holes, the warping of space-time, theories about time travel, and the notion of "now": the division of past, present and future. From the inevitable "what existed before the Big Bang" to the Hartle Hawking theory, Wormholes, time dilation, etc, much is covered about time. Here are some of the subjects you will be able to read about: 1.Tachyons: Davies wonders if Tachyons can be ruled out. The special theory of relativity has been tested to unprecedented accuracy, yet tachyons are a problem. Allowed by the theory, they bring with them all sorts of unpalatable properties. 2.Black holes: Could there be really an end to time-a singularity- and the centre of all black holes? Can they form tunnels to other universes, or can we use them like wormholes that thread back into our universe? What happens to matter falling in them? 3.Time Travel: Just a fantasy? The investigation of exotic space-times that seem to permit travel into the past will, according to Davies, remains an active field of research, but there are no realistic time-travel scenarios known. But as with Tachyons, the absence of a no-go proof forces science to keep it on the agenda, along with the usual paradoxes, of course. :-) 4.Quantum questions: Davies spends some pages describing the wonderland of weird and perplexing temporal teasers in the quantum domain. The way relativity of time fits uneasily into the quantum picture of a world where the collapse associated with measurements occurs abruptly at specific moments. The measurements of time itself are fraught with problems, since all clocks are physical objects afflicted by quantum fuzziness. 5.The Origin of Time: You'll also be able to read about the usual topic of how time originated, with all sorts of questions concerning causality, God and eternity. The Age of the Universe: Davies spends some time on the measurements of the expansion rate of the universe, which combined with realistic assumptions about dark matter lead to the absurd conclusion that there are objects in space older than the universe itself. What's going on anyway? These are just some of the main issues. This title is definitely only for those who have questioned time. Davies book is a bit dry sometimes, and can probably bore the reader who is expecting more impact. Some parts like the explanation of the quantum eraser dreamed up by physicist Marlan Scully might be a bit challenging for those with no background in the subject, but in general, the whole book is very readable and clear. Little math is required, if you know how to square a negative (imaginary number), you probably know enough to keep up, almost no math is presented. And to help, we have Davies sense of humour; while it might annoy some readers, I thought it was helping the book to flow better. It all depends on who's reading. :-) The book has good recommended Bibliography, and a decent Index. Unfortunately, there is no glossary. If I had to summarize the book in a paragraph, surprisingly, I would perhaps just write that we probably don't know much. Despite all the progress of the past decades, Time is still a mystery, and the revolution that Einstein started is still very incomplete. His word on the subject won't be the last. Unfortunately, this book ends up raising more questions than those it answers. Not Davies fault, it's really the subject itself. :-) Very interesting work for the layman who is curious about time.
Rating:
Summary: Breathtaking even at a superficial level.
Review: This is a highly ambitious book about time from the physicist's point of view (there is even an interesting chapter from the psychologists viewpoint). The concepts it deals with are profound, and sometimes absurd (cf. the paradoxes of quantum physics). The book is well organized and well written, but at the same time I don't believe that Davies has a special gift for explanation. I could follow much of what was being said at a superficial level, and even at a superficial level it is breathtaking. My biggest disappointment? Davies spends a fair amount of time on a concrete example of a case where one twin rockets into space and returns, younger than the other. I reviewed the simple math in detail, but was still confused. I think the problem is that as part of the example you need to separate the delay effect (the light coming from a star left years ago), from the time dilation effect (due to relativity), and Davies never bothers to show how this is done.
Rating:
Summary: Its as good a description as you can get for a layman
Review: This is a weak, and at times annoying book. Yes, it does have a "layman's" explanation of relativity, but not any better than can be found in many other books. Davies provides painfully detailed explanations of the simplest concepts, yet gives very little attention to explaining the more complex topics or conclusions. Davies' frequent references to his other books made this one seem like an "info-mercial," whose sole purpose is to sell his other books. One section deserves to be singled out for derision. Following a laughable chain of logic, he concludes that the human race will soon come to an end. Why? Because if the human population were to continue to increase at the present rate, it should be extremely unlikely that we'd be alive now, and much more likely that we'd be alive later in human history. Nevermind that his same line of reasoning could have been just as "valid" say, 3000 years ago, leading people to conclude then that we wouldn't be around today. If you're looking for a good, readable explanantion of time, space, and relativity, try Hawking's "A Brief History of Time," or the first half of the more recent "The Elegant Universe" by Brian Greene (the second half of that book is a fairly detailed explanation of string theory).
| 
