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am 19. September 2000
An entertaining, but ultimately empty book.
At times I felt like I was reading a well written adaptation of an "In Search Of..." episode (that 1970s TV show hosted by Leonard Nemoy) in the way that Paul Davies suggestively introduces popular Sci-Fi myths as credible and provides dramatic arguments from the view of the myth-makers. Don't get me wrong, as a kid I loved watching "In Search Of", but it and the quasi-science reporting shows like it aren't science and rarely (if ever) provide insight into the way the world works.
One example of what I'm referring to: Davies reports a theory proposed by Astrophysicist Brandon Carter which predicts the annihilation of human life within 8000 years (pg 258 - 264). The stated basis of the theory is essentially the "anthropic principal" and the statistical improbability that you or I should be alive "now" if humanity continues to thrive "for thousands or even millions of years" into the future. Nearly all the people who ever live will live a long time in our future, the argument goes, and given the number of human beings yet to be born, statistically, you and I would be much more likely to be born thousands of years from now... unless our "escalating population is soon to be chopped back, perhaps by a sudden catastrophe".
Not only does this argument mis-apply the "anthropic principal" (in that, if you were designated the 15th human being to grace the planet, you might equally conclude using this reasoning that the human population would probably be dramatically "chopped back" before the end of the first century if not at least by the twentieth century) but moreover the statistics rely on the belief that if you weren't alive "now" that you must then be made to live at some other time ... a big assumption that is not recognized by the author.
After reading the first few chapters of this book I had a sense that I was gaining a much better understanding about the nature of Time and Relativity... at least from a layman's perspective and as understood by today's science. But by the end of the book I had doubts that anything stated in this book was covered accurately or fairly. The above example is just one of many examples as previous chapters' assumptions are used to build arguments for subsequent chapters. It all builds to a head in the last few chapters of the book... a weaving mess of arguments built on weak foundations.
My rating may seem a bit harsher than this book deserves given that it is a well written, entertaining, and thought provoking book, BUT as a science book, an educational book, I think it stinks and it deserves beratement.
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am 19. November 1998
If you've ever wondered what is time, where did it come from, does it flow, why does it seem to go in one direction, will it have an end, or is it slowing down, you'll not find your answers in Paul Davies' book "About Time." Neither are you likely to find your answers anywhere else. For me, the most profound knowledge that came from reading Davies' book is the reminder that we really don't know what time is. We live in it, experience it, but really - on a fundamental level - fail to comprehend it.
Davies has subtitled his book "Einstein's unfinished revolution," and he does an excellent job of exposing the reader to some of the unexpected (from a common-sense point of view) conclusions we draw about time from the special and general theories of relativity. He offers an interesting historical perspective on the life of Einstein, and how he developed his theories. Davies also provides some interesting background on experiments that have validated Einstein's space-time, reviewing the qualitative results from some of the more important experiments.
After this introduction to the non-universal time of relativity, Davies takes us to the ultimate time machine: black holes. He offers some interesting explanations about what an imaginary traveler to a black hole might see looking out, and how we - looking in - might view the hapless victim as she neared the event horizon.
As the book progresses, conclusions and examples become less and less concrete. Relative time is a proven fact, and most physicists consider black holes a foregone conclusion. From there, Davies takes us to the very root of some of the biggest issues in cosmology: the origin of time and the age of the universe. Davies clearly believes there are problems with the current Big-Bang theory of the universe, and proposes Einstein's cosmological constant as one possible solution.
Things get weirder still. From cosmology he moves to quantum time and the implications of tunneling and EPR experiments. There is some brief mention of Hawking's imaginary time and, of course, no book on time would be complete without a chapter on possible time travel. Davies looks at all the possibilities, and some of the discussions and speculation runs wild.
For the most part I really enjoyed this book. It is well written, and clear, but sometimes the author fails to define terms properly. He appears to use the term "timewarp factor" synonymously with "time-dilation factor" but the formula on page 58 disagrees with the top figure on page 61. Also, in his discussions about problems with the Big Bang theory, I felt the author failed to give sufficient coverage to inflationary models of the universe that might resolve some of the issues he raised.
Overall, Davies' book is worth the time to read it. It may not answer all the deepest questions about time, but it will help you appreciate how little of the subject we truly comprehend. I'd also recommend his book "The Last Three Minutes."
Duwayne Anderson
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am 5. Juli 2000
"About Time" is a wonderful popularization of the of the problem of time as it is found in physics. Davis takes us step by step from a brief overview of how traditional philosphers dealt with time to the modern understanding of time that emerged as a consequence of Einstein's relativity.
It turns out that modern physics has so far not been able to give definitive answers to the most interesting questions about time: Is it in some sense independent of the observer, or is it all in the head? Why does the arrow of time always point toward the future? Is time travel humanly possible? We learn along the way, however, that contemporary physics has begun to close in on these questions, and the insights come not only from relativity, but also from thermodynamics, statistical mechanics, and quantum mechanics. Einstein's revolution is still unfinished, partly because the mainstream of physics since Einstein has been preoccupied with areas other than general relativity. But now this detour from relativity may prove very productive, as findings from these other areas have the potential to contribute significantly to our understanding ot time. The theoretical possibilities described by Davis are astounding. I read the section about antiworlds four or five times, for I could not believe my eyes--it was that fascinating. We live in a universe that is still largely undiscovred, and there may be an infinity of universes in existence: some similar to ours, others as different as one can imagine. Astrophysics today is a field pregnant with earth shuttering discoveries. And Davies' book is a superb introduction to the field and the concept "time" in particular.
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am 15. Mai 2000
"About Time" is an excellent book. Written by the Aussie Philosopher, Stephen Paulus, this is one great book that talks about time in a frank way. It's peppered with great, sometimes hilarious quotations from everyone to Yogi Berra to Eddington to Einstein to Shakespeare and more. It makes you very comfortable in taking in what Paulus is telling you. And just when it seems you're wanting to ask him a question about what he's talking about in a particular passage, there are special questions that Paulus asks himself as the reader that he then goes on to elaborate and explain for you. This isn't some egghead book written by a triple Ph.D. in a subject you've never heard of. The Philosophical side of Paulus lends a softer edge to the book. It is talking about adavanced physics concepts in some parts, so be ready to have beefed up on your gluons, kaons, and every flavor of Quark (If you pretty much instantly recognize the terms I've just used, push the buy button now!) althogh you never have to do any number crunching in your head. The only thing that might happen is that your brain will find itself uncomfortable as it digests and simply tries to come to terms with what is being said, as in "A Brief History of Time", because the concept, while easily understandable, are mentally obtuse at some times. Of course, this is in no way a bad thing. What was the book you read that fundamentally changed the way you percieve time and space around you, not just as a person, but as a member of the universal scheme.
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In this book Paul Davies provides a comprehensive, brilliant discussion of the nature of time. Beginning with Einstein's revolution which abolished the classical view of absolute time and space, Davies ranges widely into the scientific and philosophical ramifications of relativity. The bottom line is that our "common sense" notions of past, present, and future and our perception of time as flowng from present into future are distortions of reality. Instead of a flowing time that moves from present to future, time is actually a block of past, present, and future that is simply "there." The common sense notion of past, present, and future must be discarded if we are to understand the nature of time.Davies' discussion of time is exhaustive. And, while the book is difficult, particularly to a non-scientist like me, Davies has a gift for explaining very complex ideas in a way that a layperson can comprehend (but with effort; this is not casual reading!). Davies' prose is elegant and clear. He provides interesting insights into the lives of major scientific figures, particularly Einstein. And, he has a likable sense of humor. This book was a JOY TO READ.
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am 27. Mai 1998
Davies has managed to capture the very essence of physics, and at the same time explains it so clearly that it feels like reading a novel. I bought this book in December of 1996, I was 17 at the time, because I have laways had a flair for the dramatic and seemingly immposible like time travel. Davies not only convinced me that it is actually possible to accomplish time travel and how it can be held in our hands to mold it, but also kept me thinking that in time and with technology constantly increasing, we will soon capture the universe itself. Davies introduces to the reader the bigger picture, how we are so insignificant in our own universe and how we must prevail to understand it like Einstein did. "About Time" is so gracefully and fluidly written that anyone with interest for science or physics can understand even the most complex situations such as the Theory of Relativiy. I highly recomend this book to anyone, it is one of the best books written in the field.
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am 21. November 1999
As a Christian with an interest in the natural sciences, I found this a fascinating journey into "flexitime." Davies' treatment of Einstein's theory and subsequent related work provides an eloquent summary regarding space-time equivalence and the ramifications for our universe.
I have a natural bias because I accept the Bible as God's Word -- authentic and inerrant -- but I found areas of "overlap" between Davies discussions and Biblical truths fascinating. For example, the physical universe and time cease to exist inside the center of a black hole. Could this be a gateway between the physical and spiritual realms?
I may not agree with everything, but it does make you think. Davies has a firm grasp on his subject. This book is intriguing reading, and is definitely better than science fiction! I highly recommend it.
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am 24. April 2000
Dr. Davies, although profoundly eloquent, doesn't add anything new to the peculiar notion of "Einstein's Time". The book starts out strong with an overview of what was put forth in the late 19th and 20th centuries, but stalls when asked the question "what have you done for me lately". I found the total lack of anything mathematically orientated suspect. Perhaps Davies own views and interpretations of others' work are hidden behind the smoke and mirrors of tremendous vocabulary, which inevitably transformed into hopeless banter. All and all, if this book ended around page 100 (out of 300 or so), it would be stronger. If you enjoy essays of this length, pick up this book, the price is right.
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am 27. Mai 1996
Have you ever asked what time is it? Paul Davies takes 300
pages to answer this question and leaves you wanting 300 more.
From Einstein's theory of relativity to the time dilemmas
of today, this book offers startling insight on a subject many
mistakingly believe conclusive. You'll learn why time travels
faster at heights, whether or not time travel is possible, and
of mystical particles known as tachyons. Presented in a clear
and readibly understandable tone, About Time will make looking
at your watch a whole new experience!
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am 26. Mai 2005
The author goes into all aspects of time, including negative time and time reversal. He makes the relative aspects of time easy to understand, including entanglement, which Einstein thought of as "spooky" effects at a distance. The idea I found most enlightening was that each of us lives in his/her own time and that it accompanies us where ever we go.
A super read, I couldn't put it down.
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