The Holy Grail of modern physics is the search for a theory of "quantum gravity." It is a search for a view of the universe that unites two seeming...
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Nov 26, 2010
Nicholas
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An amazingly lucid book evenly dealing with different approaches to unify quantum mechanics and general relativity in a theory of quantum gravity. Smolin is very straight-forward and presents his ideas in an interesting, provocative and intelligent manner. I've struggled to understand how space can be quantized for three months, and I think I finally have some solid explanations. Smolin also does well with the Holographic Principle, which is about a difficult subject as you can come by in moder
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Oct 16, 2009
Huyen
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a nice, easy intro into quantum gravity for the interested: http://homepages.ecs.vuw.ac.nz/~visser/S...
This book isn't too bad but I don't think I retain much. the feline analogy and cosmological evolution are cute ideas, and the black hole stuff is fascinating. but much of it is extremely speculative and cryptic rambling. Or maybe I just get more cynical of theoretical physics day by day. That's fine, and at least Lee Smolin acknowledges that it is speculative, but at least don't be More...
This book isn't too bad but I don't think I retain much. the feline analogy and cosmological evolution are cute ideas, and the black hole stuff is fascinating. but much of it is extremely speculative and cryptic rambling. Or maybe I just get more cynical of theoretical physics day by day. That's fine, and at least Lee Smolin acknowledges that it is speculative, but at least don't be More...
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Jan 28, 2012
Steve
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Probably one of the most readable books about the extremes of the universe I've come across. I was grabbed by the opening questions "Is space infinitely divisible?" and half a dozen more. he goes on to explore the very small to the very large and to look at the consequences of what we can see, how we can see it and where we are and might be in the universe.
I passed it along to some Christian friends who enjoy advanced science - you might think that a book of superb science, More...
I passed it along to some Christian friends who enjoy advanced science - you might think that a book of superb science, More...
Jul 06, 2009
Mrs_M
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This book is an attempt to join quantum mechanics with the larger world and energies of gravity. The major source of debate in physics today is joining the world of the huge into the world of the small with a theory that binds them together. This is Smolin's attempt to explain the problem and how physics are attempting to solve it.
I still left this book with just as many questions or perhaps more than I had before I went in. That's not always a bad thing.
I wish I could More...
I still left this book with just as many questions or perhaps more than I had before I went in. That's not always a bad thing.
I wish I could More...
Aug 11, 2011
Xiaomin
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Lee Smolin is certainly one of the best scientists in this field and probably the only one (at top level) who can also write for general public without annoying experts in this field. As a physicist, I rarely read any science book for general public because of the intentional misconceptions (to aid broader understanding) and misrepresentations (to help generate public interest). However, in today's society, we desperately need more scientists writing more for general public for PR reasons and fo
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Aug 18, 2008
Kev
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I cannot adequately express how amazing this book is. If you are at all interested in physics -- and I am! -- this is a very important one to read. If you read "The Evolution of Physics" & "Relativity: The Special & General Theory" by Einstein, "Chaos" & "Genius" by Gleick & "Feynman's Lost Lecture" by the Goodsteins, then, read this one ... you will be in a position to reevaluate all of the known unviverse as we understand it right now.
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Feb 16, 2009
DJ
rated it:
Lee Smolin stormed his way onto my fantasy grandfather list the fateful summer of 2008 when I realized physics and I were more than just a fling. His The Trouble with Physics was a fatherly introduction to the current state of the edges of theoretical physics and I was hooked. Needless to see, I was ecstatic to find "Three Roads to Quantum Gravity" under my Christmas tree this year and devoured it on plane ride to Thailand soon after.
"Three Roads to Quantum Gravity" More...
"Three Roads to Quantum Gravity" More...
Oct 01, 2007
-uht!
rated it:
This is one of the small list of books that has forever changed my paradigm. Unlike the other ones, I was aware of the paradigm change as it was happening and I could not put this book down.
"...the first principle of cosmology must be 'There is nothing outside the universe' . . . This first principle means that we take the universe to be, by definition, a closed system. It means that the explanation for anything in the universe can involve only other things that also exist in th More...
"...the first principle of cosmology must be 'There is nothing outside the universe' . . . This first principle means that we take the universe to be, by definition, a closed system. It means that the explanation for anything in the universe can involve only other things that also exist in th More...
May 02, 2008
Ethan
rated it:
Some sadness. The very first words on the back cover of the paperback edition, after PHYSICS, are:
"The Holy Grail of modern physics is the theory of 'quantum gravity'. It is a search for a view of the Universe that unites two seemingly opposed pillars of modern science..." et cetera. Let's unpack these two sentences. The first mentions the Holy Grail, which I think is not the right analogy for a mathematical description of spacetime. I seem to remember the Holy Grail as th More...
"The Holy Grail of modern physics is the theory of 'quantum gravity'. It is a search for a view of the Universe that unites two seemingly opposed pillars of modern science..." et cetera. Let's unpack these two sentences. The first mentions the Holy Grail, which I think is not the right analogy for a mathematical description of spacetime. I seem to remember the Holy Grail as th More...
Jan 31, 2012
Mark
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I really liked this book because while the author makes no bones about what he believes, he brings together N Theory and Loop Quantum Gravity, as well as the combined view that some adhere to, talking about all three view points without really stating that any one avenue is wrong. He essentially takes that stand that he believes X, but that Y and Z are both possible, and gets into pretty good descriptions of X, Y, and Z concepts. It really made me want to go back to school again!
Sep 24, 2007
Rob
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this book is so dumbed-down that i seriously considered putting it on the "non-fiction for humans" shelf. the absolute nadir came when he used as his analogy for the superposition principle of quantum mechanics a mouse which, when eaten by a cat, might turn out to be either "tasty" or "yukky". Yukky? Yukky? forget that it's universally spelled "yucky". but he hammers away at his analogy and the reader is subjected to the word "yukky" several
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May 07, 2009
Manny
rated it:
Lee Smolin is one of the most interesting and controversial figures in modern physics. Establishment physicists often call him a maverick or worse. I am one of many laypeople who think that he's telling it like it is, and the mainstream people are full of s...trings.
When he wrote this book, around 1999, I think he was more part of the mainstream. He presents several different approaches to the very difficult problem of unifying gravity and quantum mechanics. It's clear that his hear More...
When he wrote this book, around 1999, I think he was more part of the mainstream. He presents several different approaches to the very difficult problem of unifying gravity and quantum mechanics. It's clear that his hear More...
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May 16, 2009
Peter
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A lot of what's covered in the various pop physics books is all the same stuff over and over, but the proposed extensions to contemporary physics explained in this book are nothing I've read anywhere else. I like that it covers string theory realistically, neither treating it as the one true way, nor as being void of value just because it's flawed.
Jun 12, 2008
Jim
rated it:
Either I'm getting progressively dumber, or the books I'm reading are getting progressively harder for me to understand. Hopefully it's the latter of the two. I enjoyed this book in principle, however there was a lot that I had trouble understanding. I think I was able to grasp the basic ideas behind most of the theories mentioned, but some of the finer details may have been lost on me.
Still, Smolin does give very detailed explanations for the different versions of String Theory, Loo More...
Still, Smolin does give very detailed explanations for the different versions of String Theory, Loo More...
Jan 28, 2011
Ravi
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Always had a problem understanding time. This book solved that problem.
Loved the book, simply written for someone with an understanding of physics and chemistry. This book brought me up to date with developments since I had ceased to be actively involved in learning science.
Loved the book, simply written for someone with an understanding of physics and chemistry. This book brought me up to date with developments since I had ceased to be actively involved in learning science.
Jul 17, 2010
Joseph
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Smolin's weakest contribution. He doesn't give the reader enough credit, I think, i.e., he doesn't go into enough detail to make the book truly worthwhile. I would definitely recommend this book to the completely uninitiated, but beyond that, no.
Aug 11, 2011
Kam-Yung
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An interesting book by Smolin that offers three ways that Quantum Mechanics and Relativity could be combined to produced the unified Quantum Theory of Gravity. All three ways currently give an incomplete view of the Unified Theory and only time will tell if one ever emerges. But the journey is fun, and requires you to rethink the concepts of space, time, information and the connections between events.
Jul 07, 2010
Kathrin
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I'm very interested in physics but by no means a pro... I find his book very interesting, some parts are a bit confusing for me but even for a beginner pretty easy to understand for the most part ! I'd say if ur interested in this subject its a good read !
Aug 24, 2010
Carolyn
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I used to consider myself the "intelligent layperson" this book was intended for. I've been forced to self-demote. No worries. The 25% or so I was able to grasp was good stuff.
Sep 15, 2008
George
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This book is truly well written and provides a description of the nature of space which invites further thought..."space indeed is not empty! Many of the ideas about space I also have thought of are in this book...perhaps, I'm smarter than I previously have given myself credit for.
Jul 31, 2007
Amanda
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this is pretty obscure and probably not something that someone unfamiliar with quantum gravity would enjoy but it's profound (and profoundly understated) and had a huge influence on me. in my copy the pages are falling out from being read so many times!
Feb 12, 2008
Jason
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Excellent edge of physics book. Discusses loop quantum gravity, string theory, and another theory. Even if science moves forward to answer questions, very lucid account of where we are and thoughts on how we got there.
Aug 18, 2007
Alex
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Science, specifically physics, arguably represents the times better than fashion or art; it's the limit of human perception at any given point in time. This is a lucid explanation of a few modern gravitational theories.
Dec 02, 2010
Patrick
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Good information. Got a little dry in the middle but had a lot of good perspective for anyone interested in the topic.
Dec 27, 2010
Ilya
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Can a physicist, however brilliant, explain string theory, M-theory and loop quantum gravity to the lay reader in a 240-page book? I don't think so. However, he can boost the reader's self-esteem by giving the reader the impression that he (the reader) understands these three theoretical frameworks.
Feb 13, 2012
