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652 of 692 people found the following review helpful:
5.0 out of 5 stars
The string theorists were scammed!, September 25, 2006
This review is from: The Trouble With Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next (Hardcover)
The part of the book I found most interesting was the part which tells how the string theorists were scammed by Nature (or Mathematics). Of course, Smolin doesn't put it exactly like this, but imagine the following conversation.
String theorists: We've got the Standard Model, and it works great, but it doesn't include gravity, and it doesn't explain lots of other stuff, like why all the elementary particles have the masses they do. We need a new, broader theory.
Nature: Here's a great new theory I can sell you. It combines quantum field theory and gravity, and there's only one adjustable parameter in it, so all you have to do is find the right value of that parameter, and the Standard Model will pop right out.
String theorists: We'll take it.
String theorists (some time later): Wait a minute, Nature, our new theory won't fit into our driveway. String theory has ten dimensions, and our driveway only has four.
Nature: I can sell you a Calabi-Yau manifold. These are really neat gadgets, and they'll fold up string theory into four dimensions, no problem.
String theorists: We'll take one of those as well, please.
Nature: Happy to help.
String theorists (some time later): Wait a minute, Nature, there's too many different ways to fold our Calabi-Yao manifold up. And it keeps trying to come unfolded. And string theory is only compatible with a negative cosmological constant, and we own a positive one.
Nature: No problem. Just let me tie this Calabi-Yao manifold up with some strings and branes, and maybe a little duct tape, and you'll be all set.
String theorists: But our beautiful new theory is so ugly now!
Nature: Ah! But the Anthropic Principle says that all the best theories are ugly.
String theorists: It does?
Nature: It does. And once you make it the fashion to be ugly, you'll ensure that other theories will never beat you in beauty contests.
String theorists: Hooray! Hooray! Look at our beautiful new theory.
Okay, I've taken a few liberties here. But according to Smolin's book, string theory did start out looking like a very promising theory. And, like a scam, as it looks less and less promising, it's hard to resist the temptation to throw good money (or research) after bad in the hope of getting something back for your effort. One of the questions Smolin addresses in the rest of the book is why the theoretical physics community has kept with string theory and largely abandoned all the other approaches to quantum gravity. The short answer is that it's hard to admit that you've been scammed. The long answer is much more complicated. Another thing Smolin addresses in the book is other approaches to quantum gravity. And as could be predicted, he gives lots of space to his own approach and too little space to others, especially Alain Connes' non-commutative geometry. But overall, I found it very worthwhile and entertaining, and a good explanation as to how theoretical physics came to be in the state it is today.
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328 of 346 people found the following review helpful:
5.0 out of 5 stars
Fantastic reading, September 11, 2006
This review is from: The Trouble With Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next (Hardcover)
I never write reviews for books I buy here although I've read virtually every popular theoretical physics book for sale on amazon; however-- the bizarre negative 'ad hominem' reviews for this book have forced me to say something. I was looking forward immensely to the release, in fact I pre-ordered it, because Lee Smolin's earlier "Life of the cosmos" absolutely captivated me way back when. And I must say, "Trouble with Physics" was so interesting and filled with intelligent ideas I couldn't put it down from the moment I bought it, even reading it while walking home like back when I was in high school...
As stated in the book descriptions above, it reviews the past 30 years of theoretical physics and then concentrates on the fact that little progress has been made in that period towards a 'final theory'. And when you think about it, he's right! The problem of unifying quantum mechanics and relativity is already more than half a century old! And so the book discusses why he thinks string theory has failed, and why physics needs a kind of soul-searching to regain its path, aided by experimental results.
I remember well the 'hype' for string theory a few years ago, it was expected to lead to a theory of everything pretty quickly, which obviously has not happened. I'm assuming the negative reviews of this book are from the string theorists, since there is nothing wrong with the cogency or pertinence of Smolin's arguments. String theorists seem to be oddly over-confident they are on the right path, and Smolin is willing to ask if they are not a bit self-deluded on that count. It does seem like a bit of a rejection of Occam's razor, to be positing multiple dimensions, and a multi-verse, when in the end very little has been truly explained... who knows, in the end?
The last part of the book deals with the sociology of academic physics in university depts., and I must admit is slightly less interesting, and more polemical, than the sections that speculate on what a 'final theory' might look like.
Some of these concepts-- such as the variable speed of light theory, or that relativity may not be the full truth, the huge mystery of the cosmological constant and its explanation, are really heretical and for that reason, immensely entertaining!
So, in conclusion, very enjoyable for the 'layperson' who is not committed to believing in string theory and is willing to open their minds to very intelligent speculation on a final theory.
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109 of 118 people found the following review helpful:
5.0 out of 5 stars
A must read for people who care about fundamental physics, September 18, 2006
This review is from: The Trouble With Physics: The Rise of String Theory, the Fall of a Science, and What Comes Next (Hardcover)
Fundamental physics has been exceedingly successful for over two centuries. The rapid advances in our understanding of natural laws in the first three quarters of the 20th century were just as breathtaking as those in microchips or hard drives in the last. But this progress came to a screeching halt 30 years ago. There has been no real progress since the establishment of the standard model.
To observers outside of the physics community, this fact is far from obvious. Theorists in fundamental physics continue to make announcements on new ideas and results. Books are written and TV shows are made to trumpet the progress in string theory. Many models based on string theory are taken and marketed as facts.
As years and decades go by and waves of string theory "predictions" are repeatedly superceded by new, incompatible ones, doubts begin to grow in the minds of knowledgeable outsiders. How can a "theory of everything" that completely describes an "elegant universe" keep contradicting itself on issues as basic as the dimensionality of spacetime? How can the string theorists be so sure of what happens at 10^19 GeV while being totally silent on the physics just beyond the standard model at 10^3 GeV? How can 30 years go by and nothing in particle physics theory is remotely Nobel-worthy? How can the two most important experimental results (non-zero neutrino masses and a positive cosmological constant) catch string theory by such surprise?
Inquiries regarding these and many other suspicious signs are stonewalled by string theorists. The person who raises the issue is inevitably called ignorant, stupid, malicious, anti-science or all of the above. There are just too many beautiful results in string theory to be explained by coincidence, we are told. String theory is just too vast and too deep for human to comprehend easily, they assure us. Trust us, they say, this is not a case of "it is difficult to get a man to understand something when his job depends on not understanding it".
But they did not address any of the questions. Worse, the list of questions grows longer by the year. Is the universe a 4-dimensional brane floating in the extra dimensions or a glorious 10-(should it be 11 now?)dimensional spacetime with 6 of the dimensions curling up? Why 6 and not, say, 7? If there are countless numbers of ways to curl up the extra dimensions, does each way correspond to a string universe? All these universes cannot be real at the same time, can they?
As the string story gets stretched thinner and thinner, so is its credibility. After it became increasingly clear that string theory would never be capable of making any meaningful predictions, the final straw, for many objective observers, finally fell when a large faction of string community pushed for the wholesale adoption of the Cosmic Anthropic Principle, an erstwhile anathema of modern science. String theory is too important, they claimed, to be bounded by conventional scientific principles, very much the same way in which Envon executives claimed their business to be too innovative to be understood with conventional accounting methods.
Just like the couragous independent analyst who started to question Enron's business practice a year before its ultimate collapse, Lee Smolin (along with Peter Woit) provides a stinging early indictment of the self-propelling enterprise that is string. You will find answers to or at least detailed descriptions of all the aforementioned questions and much more.
To me personally, the biggest surprise came when Smolin exposed the fraudulent proclamation of major achievements in string theory: the finiteness of its perturbative series, the S-duality, the AdS/CFT duality, the derivation of the classical general relativity equation and the computation of black hole entropy. Despite early misgiving about some shaky premises of string theory, I had nonetheless admired my string colleagues for their unparallelled breakthroughs. It turns out that these breakthroughs are nothing more than unproven hunches that somehow became the foundation and justification for decades of dominance over particle physics along with tens of thousands of self-congratulating publications. And you call this a theory more important than science itself? Shame on you!
After giving excellent diagnosis and prognosis on how sick fundamental theoretical physics has become, Smolin uses the final third of his book to prescribe a remedy. Here his arguments falter a bit. He advocates shifting emphasis away from calculation to philosophical deliberation, but with the exception of Einstein's General Relativity, physics has never achieved significant advance through abstract philosophical pursuit. The key to salvation from 30 years of wild goose chase lies in new experiments. Fortunately, the LHC will be operational soon and a new generation of physicists will have something real to work on. With some luck, string theorists will find themselves superceded by old fashion science within the next few years, and the readers of this book will understand why it is such a good riddance.
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