Excellent read. Smolin's critique of string-them-along string theory in What's Wrong with Physics is greatly superior to Greene's cheerleading treatment of the same topic in The Elegant Universe. It is interesting the way that physics is being corrupted in a similar way to the financial system in the current crises causing a meltdown on Wall Street: people spewing out equations that nobody really understands and that have little relation to reality. But Smolin, while enlightening in his insider insights into the achievements and failures of string theory, falls into many of the same faulty assumptions of contemporary physics. My own view is that special relativity was fairly brilliant, but general relativity is essentially flawed. Physicists pay too much homage to Einstein, without admitting that he could be wrong. Remember that nobody has ever found a gravity wave, but general relativity appears to be premised on their existence. It would be more profitable to seek to create a theory that explicitly makes gravity waves impossible than to continue to believe in any theory where they exist. And the entire program of unification is suspect. Why should the Universe require unification when everything we know points to simply finding, over time, that it contains more and more things and phenomena -- different laws at different scales of spatial dimension -- and becomes bigger and bigger than we ever thought before? The Universe seems to require diversity, not unification. And while physics flounders, there are legitimate advances in related fields: our understanding of the information sciences and the concept of entropy appear to be critical for any advances in physics.

about the sociology of science, and I agree completely with what it says about it, and on the need to parcel funds and scientists more equably among the several possible approaches (for example, to fundamental physical theories). The trouble is that men are not angels, and the proposals it makes are very difficult to implement in practice. Perhaps, as Churchill said of democracy, the present system in science "is the worst possible one, with the exception of all the the others". Or, paraphrasing Juvenal 2,000 years ago: "Who'll watch over the fairness of the funds' and careers' administrators?". It really looks like an infinite regress. So perhaps the only feasible solution is to muddle through, as the human race has done over its entire history.

Other reviewers have spoken at length about the book's contents, and I will not repeat them. Suffice it to say that I don't feel qualifided to judge the relative merits/defects of string theory versus loop quantum gravity and the other "theories" that are being worked upon, although I am sympathetic to those who start from relativity, I think the "background independence" argument has some merit, and string/M theory is, in my opinion, beginning to sprout epycicles. You don't need to have worked on it to realize it. Of course I could be wrong: in this (or these) Universe(s) almost anything is possible, which, although a very trite remark, is deeply true.

But this book, although eschewing math, is written for an adult public -unlike so many ones in the market today-, doesn't simplify the issues (i.e., doesn't pretend you can really "understand" anything much without math), depicts accurately why science isn't exactly what you thought it to be, but instead in the short run (say 1½ human lifespans?) much more based on personal vanity and lust for power than on rational considerations, and, more importantntly yet, is CIVILISED. It's really refreshing to read pages unpolluted by vicious ad hominem attacks à la Lubos Motl (a learned physicist who reviewed, among others, Peter Woigt's also excellet book "Not even wrong ... "), even if it's only for appearences' sake.

For those of us non-physicists looking into what has been going on in string theory for something close to three decades, things just look curiouser and curiouser. No doubt the problem is that only physicists can comprehend the science itself. Still it is enormously frustrating that not a single shred of experimental evidence has come to light supporting string theory. What this suggests is that string theory, as beautiful as it may be, is art not science, or perhaps it is pure mathematics.

Lee Smolin, who is a real physicist, has come to a similar conclusion in this insider's look at the sorry state of particle physics today. Once the undisputed master of the sciences, physics has become--it is downright dreadful to acknowledge this--the butt of jokes from--are you ready for this?--the social sciences! Even professors of literature are having their way with physics. The inability of the string theorists, who have dominated particle physics lo these many years, to accomplish anything substantial, has so damaged the prestige of physics that something called postmodernism has been able to declare that all of science and mathematics constitutes merely an arbitrary "social construction" with no more claim to objective truth than utterances from a creationist's convention.

Say it isn't so, Brian Greene. Well Professor Greene has said it isn't so, but entrenched scientists tend to have entrenched ideas, just like global warming deniers, and so what we need are some hard facts derived from experiments or at least some predictions that can be identified and confirmed. Alas, as Smolin is at pains to point out, we have more like the opposite.

Take the reincarnation of Einstein's cosmological constant. Not predicted by string theory. Take the discovery of dark energy. Not predicted by string theory. Take the seven additional dimensions required by M-theory (an offshoot of string theory), and the old phobia about infinities in the equations seems rather mild. No one has yet seen, tasted, smelled, felt or heard even a fifth dimension (putting aside the once popular band) let alone six others. We cannot even imagine such a thing.

Well, yes, the fact that we can't imagine them doesn't mean they don't exist. However, one of the leading reasons that physicists like string theory's extra dimensions is that they do away with the infinities. Talk about going from the frying pan into the fire, or from the deep blue sea to the devil!

Philosophy was once the most prestigious academic discipline. Could the same thing happen to physics? And if so, why?

Part of the problem is the great success and power that physics has enjoyed since the days when Newton stood on the shoulders of giants. Even more so, since the days of James Clerk Maxwell, vast has become our knowledge of the physical world. Indeed physics and physicists have constructed much of the modern world. Their ideas and discoveries and understanding have led to enormous advances in technologies that have increased the standard of living of people, at least in the developed nations. So much success has led to great expectations. The sad fact for physics may be this: the next great discovery may be centuries away, or worse yet, beyond the reach of humans.

Smolin certainly isn't so pessimistic. The tone of "The Trouble with Physics" is that of a father urging his children to great accomplishments while warning them that they have been wayward. He is blunt but bends over backwards to be fair. The trouble with the book for non-physicists is that it is really impossible to follow the various arguments for and against string theory in any concrete detail. The truth is in the equations, and Smolin doesn't give any, and rightly so since this is a book aimed at the educated general reader. We educated general readers are left skimming the bewildering details of the history and current state of string theory to focus on the broad implications while being guided by Smolin's expert opinion. But even in reading somebody like the aforementioned Brian Greene, who is a proponent of string theory, this reader at least was left with the sense of watching a wild goose chase from a distance.

It isn't just in particle physics that physicists have gone over the deep end, so to speak. Take cosmology where some physicists are postulating a large, possibly infinite number of universes in addition to the one in which we live. As Smolin points out "The existence of a population of other universes is a hypothesis that cannot be confirmed by direct observation..." He adds, "...the fact that we are in a biofriendly universe cannot be used as a confirmation of a theory that there is a vast population of universes." (p. 163)

Although there is nothing wrong with Smolin's writing style, and he does write with a minimum of jargon, some of this is impenetrable, at least for me. Those more versed in physics will do better I'm sure. However particle physics is per force about things we can't see and can't even visualize.

Near the end of the book Smolin presents some alternatives to string theory. As a non-physicist I have no ability to evaluate these approaches, which brings up an important point. How can any non-physicist pass any kind of judgment on the validity of string theory? We can't. We can only count noses--physicists' noses. When we do we find that most theoretical physicists believe in string theory despite the dearth of experimental support. Why? Perhaps because string theory is what they have been doing all their working lives, and string theory is what they have been taught and are teaching.

My question is, have string theorists become a sacred priesthood? Smolin doesn't use this term, but his book suggests as much.

I am still wondering why theoretical physics is behaving like it is doing...losing the essence that characterizes the scientific method. After reading this delightful and incisive book, my only concern is to know how long it will take to string theorists to accept we are following the wrong way...as physicists. I just wish this book captivates as many honest people as the honest author desires.

What shocked me most about Smolin's account of string theory is his claim that many of its leading lights have paid too little attention to mathematical rigor or even to a clean mathematical specification of their theory. If true, this is a major scandal. In most professions, this sort of sloppiness would be grounds for losing a job or even being prosecuted if something goes wrong. To hear that string theorists are perhaps not always intellectually sound is discouraging. They have raised exaggerated expectations about what their framework accomplishes (hype), and their methods have not always been sound (malpractice). Smolin is of course much more polite, and recognizes that many of the ideas advanced by string theory needed to be explored even if they prove fruitless or wrong. But his book does show clearly that something has gone seriously wrong with the internal governance of the physics profession.

Brian Green, a leading string theorist, says the following in his contribution to "The New Physics" (2006): "It might be argued that string theory has so far failed [] since it has not yet made very detailed connections with experiment." He goes on to hold out the hope that "Ultimately, the tests of the theory are likely to come from cosmological observations that detect the state of the Universe during the first moments after the Big Bang." Anyone who has read the cosmology literature knows how often inferences have to be piled on top of inferences in an attempt to arrive at a consistent explanation of what is observed from humanity's single vantage point and with our imperfect instruments. The kind of cosmology that would be needed to test string theory is not exactly around the corner. Moreover, I always had the impression that cosmologists are looking more to other branches of physics to help them make sense of their observations than the other way around.

Aside from his criticism of string theory, Smolin makes an inspiring argument for new and more diverse approaches to unsolved problems in physics, among which he includes unifying general relativity and quantum theory, establishing sounder foundations for quantum mechanics, unifying all particles and forces as manifestations of a single fundamental entity, explaining the constants used in the theory, and resolving the puzzle of dark matter and energy in cosmology. The book helpfully names and discusses a number of theorists the author thinks are currently making the most interesting contributions to solving these problems. Without Smolin's expert guidance, it is unlikely that a reader would independently come across these fascinating contributions.

The chapters on the sociology of physics will be unsurprising to anyone who has worked in academia. However, if Smolin's revelations about groupthink and sloppy mathematics in the physics profession are even half true, they raise concerns about other areas of physics as well. Given the importance of physics to the fate of mankind, at least since the invention of the atom bomb, it is clearly time to develop new principles for the governance of this essential group of brilliant, but still human and imperfect, thinkers.

Lee Smolin presents his case not for why string theory should be dropped, but why other theories should be pursued more vigorously. Rather than demonizing string theory, Smolin looks at the theory's successes and failures and then moves beyond that to discussing the sociology of science in general, and this is his main issue. Smolin says the system is set up to keep alternative theories out, while the fashionable theories get all the attention, and that this system is perhaps the reason why theoretical physics has been stuck for so long. Great book.

So many reviewers have said so many things, let me just add this: During the past thirty years, we have seen the rise of religious ideology and its disastrous effects on our political system, not to mention our national finances and national reputation.

How interesting that science has experienced the same things, the same disasters born of the same focus on ideology rather than factuality, in the same time period.

This book is the first BIG public demonstration that this period may be coming to an end.

The disaster of string theory, and the Irag war, both prove the same thing: ignoring the dictates of reason, and setting aside facts for fantasy, always leads us to the same place: nowhere we want to be!

Thank you Lee Smolin.

A must-have for anyone interested in their world. And an instant classic.

Peter Shor provides an excellent summarizing review of the first half to three-quarters of the book. But he largely skimped on what I think Smolin's main focus was, based on reading Smolin's website and the author's notes in the book, when he began the book. The last few chapters are concerning the role of academia in maintaining integrity throughout their ranks. If Smolin is correct, and this book provides excellent support to believe so, this has not been done with string theory, regardless of whether it is a correct theory or not. It is an extremely volatile subject that is likely to explode in the next few decades, and not only in physics but all academic fields.

I feel the situations is complicated, but can be roughly simplified as the selfishness and fear of a group of highly respected (and sometimes also highly paid, but not always) individuals who perceived that they were not making any progress and seek to protect their respected status through manipulation. They are essentially echoing an everyday experience - even the most ignorant person can seem quite capable if they merely exude enough self confidence. Well, according to the accounts by Smolin and many others, the string theorists are doing exactly that - holding onto excessive and unfounded confidence. Unfortunately, the first step in gaining knowledge is to admit that you already possess none.

Smolin takes a much less accusational stance than I do here, but he spends a significant amount of time in his book discussing this issue and it should not be left out of the reviews.

--G. Hill

Lee Smolin, a fair-to-middling popularizer of physics vents his anger at himself and others for pursuing the chimera of an 11 (or more) dimensional universe and a "theory" that produces 10^500 distinct theories. Unfortunately for the reader, Smolin manages not to define his terms, and gives no clue to how this number of 10^500 was arrived at, nor even what a distinct theory means.

The book is almost solely interesting for its treatment of the sociology of string theory and the way its practitioners monopolized high energy particle theory for much more than a decade.

I jumped at this title when I saw it among my Amazon recommendations (Sometimes they do get these things right.) thinking to myself, "Ah, finally somebody out there (besides Feynman) has had the courage to state the obvious and actually write a book about it." And this Smolin does here in language I think most people with a basic science education can understand. Good show Lee!

But I do have a couple of somewhat minor problems with it. The first problem is, as far as I'm concerned, Smolin IS stating what has always seemed obvious to me. Indeed, ever since viewing the PBS special on String Theory and reading Brian Greene's book regarding it, I've been saying to myself: "What a lot of twaddle! This isn't science. It's more like some terribly bad mixture of mathematics and philosophy, making for bad theories in both fields." Actually, Smolin states as much here:

"Nevertheless, it seems to me that any fair-minded person not irrationally committed to a belief in string theory would see this situation clearly. A theory has failed to make any predictions by which it can be tested, and some of its proponents, rather than admitting that, are seeking to change the rules so that their theory will not need to pass the usual tests we impose on scientific ideas." P.170

Exactly! It truly baffled me that PBS would spend all this money on what was obviously a scientific farce. One might as well watch a rerun of Jeeves and Wooster. It's much more entertaining and Wodehouse, unlike Greene et al., knows himself to be a farceur. Anyway, the minor problem is that for me the above quote is all that need be really said about it (One might throw Feynman's in for good measure.). A whole book would seem to be unnecessary. But, obviously, there are scads of others who don't see that what Charlie Rose in his interview with Greene rhapsodized about as "The Theory of Everything" is not even a Theory of Nothing. It's not even a theory.

But Smolin did write this book, which brings me to my second problem here. Smolin is what I suppose I'll call an Einsteinian, but with a twist (no String Theory pun intended). As another reviewer has pointed out, this book has two parts. The first debunks String Theory. The second rails against "group think" and the state of current academia, in the States, anyway - All good and well, so far - But the last chapters are a bit odd for a book about physics, methinks. Here, Smolin reveals himself to be, for lack of a better word, a Romantic. He loves citing examples of people whom he calls "seers" rather than "craftsmen", of which Einstein is the best exemplar. People who hole themselves up alone and work things out based on some mystical insight. In particular, he cites one particular physicist who, during a hike in the mountains, had a vision that "time is unreal" and has spent the rest of his life working things out to prove that this is so. Exactly what it would mean for time to be unreal he does not elucidate.

This brings to mind Bertrand Russell's famous essay, "Mysticism and Logic" where he notes that the unreality of time is key to almost all mystical systems and philosophies. It is not confined to physicists; indeed, it is more associated with poets. Avers Yeats:

"For one moment
While on that grey stone I sat
I knew the One is animate
Mankind inanimate phantasy."

Russell, in his essay, concurs with Smolin, as I understand Smolin anyway; pointing out that almost all great ideas start out with some sort of mystical insight of this sort. But the way the book concludes, citing all these lone anchorite physicists, toiling away in their cottages and flats, is just a tad odd for a book debunking a notion because it's unfalsifiable and lacks empirical verification. Smolin seems to concur with Thoreau here, "No one ever followed his genius until it misled him."

To sum up, Smolin, in these latter chapters, seems to be a sort of Thomas Carlyle of 21st Century physics. He's an admirer of the Great Man/Great Idea interpretation of the history of science. This view certainly has its attractions. And, certainly, we associate all scientific revolutions with particular names: Galileo, Kepler, Newton, Maxwell, Einstein, Feynman etc. I suppose they all qualify as "seers" in Smolin's view. Still, it doesn't quite square with the empirical approach, and this view of history in general has peculiar consequences. I can't get out of my mind the image of Goring reading a German translation of Carlyle's account of Frederick the Great to the Fuhrer as the Soviets close in on Berlin.

True story.

I am a mechanical engineer, so my mathematical understanding of physics doesn't go much beyond special relativity, introductory quantum mechanics and just an appreciation for what general relativity has to say about mass telling space how to curve.

Lee Smolins book is written for the lay public as well as physicists and was a very interesting and eye opening read on the great number of string theories which abound. According to Smolins, string theory is very likely just a beautiful mathematical "bookkeeping" system which can relate current observations to each other and unify some of the forces of nature.

The author is a onetime string theorist who has since left the field and insists after 30 years there have been no breakthroughs and certainly no predictions of any new particles or phenomena which can be tested. Based on what Smolins is saying it sounds to me like string theory amounts to a multi-dimensional curve fitting spline whose coefficients can be calculated and precisely tuned to rationalize just about everything we already know, but makes no new and testable predictions.

He also says that it scarcely has the needed properties to call it a "theory of everything" and that far too much time is being spent on it by too many people caught up in its mathematical beauty and elegance, something he admits it has a great deal of. The idea of subatomic vibrating, open and closed rubber bands being the ultimate component of particles and energy is very appealing to many people.

He also says that the string community spends time calculating these potentially infinite ("fit" coefficients) universes and the only test of their work is that it fits known prior phenomena. Furthermore, the only critical test a new string theory receives is peer review from a specialized community that is starting to believe that predictions of any new observations are not in the cards and we shouldn't be looking for them anyhow. When we stop requiring a theory to anticipate new observations we are no longer following the scientific method.

Until I read this book I believed, based on my faith in physics, physicists and the scientific method, that string theory was the answer to everything and only required time for it to provide some testable predictions. It has had over 30 years time and research by a disproportionate percent of the physics community. I am now not so certain that it is a valid theory, especially after some of the strongest string theorists are telling us not to look for testable predictions.

I am a mechanical engineer, so my mathematical understanding of physics doesn't go much beyond special relativity, and an appreciation for what general relativity has to say about mass telling space how to curve.

Lee Smolins book is written for the lay public as well as physicists and was a very interesting and eye opening read on the great number of string theories. According to Smolins, string theory is very likely just a beautiful mathematical "bookkeeping" system which can relate current observations to each other and unify some of the forces of nature.

The author is a onetime string theorist who has since left the subject and insists after 30 years there have been no breakthroughs and certainly no predictions of any new particles or phenomena which can be tested. Based on what Smolins is saying it sounds to me like it is a multi-dimensional curve fitting spline whose coefficients can be calculated to rationalize just about everything we already know, but makes no new and testable predictions.

He also says that it scarcely has the needed properties to call it a "theory of everything" and that far too much time is being spent on it by too many people caught up in its mathematical beauty and elegance, something he admits it has a great deal of. The idea of vibrating, open and closed rubber band like objects being the ultimate source of matter and energy is very appealing to many people.

He also says that the string community spends time calculating these potentially infinite ("fit" coefficients) universes and the only test of their work is that it fits known prior phenomena. Furthermore, the only critical test a new string theory receives is peer review from a community that is starting to believe that predictions of any new observations are not in the cards and we shouldn't be looking for them anyhow. When we stop requiring a theory to anticipate new observations we are no longer following the scientific method.

Until I read this book I believed that string theory was the answer to everything and just required the test of time for it to provide some testable predictions. It has had over 30 years time and research by a large percent of the physics community. I am not so certain that it is a valid theory; not after some of the strongest string theorists are telling us not to look for testable predictions.

If only more scientists wrote for popular audiences with the humility Lee Smolin does. Whilst it occasionally gets bogged down in the detail of its own material - there are more minutiae on particle physics here than most people will care for in a bedtime read - Lee Smolin's major points are clearly made and they ring like a bell.

In some ways this is a work of popular philosophy of science, not popular science itself: Smolin approaches his subject through the prism of the failings of string theory to coagulate over the last thirty years, but only in the loosest sense is this an attempt to prove string theory wrong and his own favoured research programme, quantum loop gravity, right. For one thing, he accepts from the outset that there are significant issues with his own programme.

Smolin's concern is more around the practice of modern physics; how the gradual disappearance of anything resembling testable empirical evidence has given way to ever more theoretical modelling which in turn has led to hypotheses of increasingly incredible (literally, that is) implications. For any variety of string theory to work (it is more of a cluster of similar possible theories, rather than a discrete theory as such) the mathematics require something like *eleven* spatial dimensions, some of which, it is variously hypothesised, must be so small as to be conceptually unobservable (the image we are invited to consider is dimensions which curl up into little donuts smaller than an atomic particle across), or which appear to require an infinity of alternative universes - a "multiverse" if you will - into which these dimensions can be projected. (I may well have not understood or expressed this perfectly: the important point is that the theory must account for the absence of any physical evidence for the extra dimensions: solution - they're invisible, of course!)

Smolin's concern is not just that these are outlandish and faintly ridiculous consequences - though they surely seem to be - but precisely that they are systematically untestable. *By definition* there is no means to measure spatial dimensions smaller than the smallest subatomic particles. *by definition* we cannot see or measure physical effects occurring outside our own universe. These are not just difficult to say with a straight face, Smolin argues, but by any commonly understood sense of the term they're altogether unscientific: logically closed, untestable, unfalsifiable, unreliant on any kind of inductively gathered argument.

Precisely the sort of arguments, in other words, that give religious cosmologies a bad name: utterly verboten, you would think in the enlightened mead-hall of the physical sciences. (Yet, and without apparent irony, biologist Richard Dawkins makes favourable reference to the "multiverse" theory in his recent book The God Delusion!)

Smolin argues that this uneasy development collides head-on with some uncomfortable realities about the sociological aspects of the practice of science. Again, Smolin is persuasive here (though in my case preaching to the choir) in citing favourably the late, anarchic, philosopher of science Paul Feyerabend, whose general message is that for scientific methodology anything goes, and all theories have a role to play for the good of the "development of knowledge", and that determined insistence on an existing accepted theory for framing ongoing research hardens quickly and dangerously into dogma: you need the vistas that different theories offer, says Feyerabend, or they are "as useless as a medicine that heals a patient only if he is bacteria-free".

For his trouble, Smolin is duly criticised for exhibiting "postmodernist" or "relativist" tendencies, and while I don't think this *is* a criticism myself, it is in any case unfairly awarded, since Smolin avowedly retains a belief in the possibility of objective truth, and promises to (but in the end doesn't really) take issue with the work of the most celebrated "postmodernist" philosopher of science, Thomas Kuhn. (I'm a fan of Kuhn's so I was looking forward to the challenge, and was a bit disappointed to find it didn't materialise).

Practically, Smolin feels that String Theory is now a "paradigm in crisis". Certainly, the theoretical tail seems to be wagging the practical dog. It is difficult to see what practical utility a theory has which postulates invisible dimensions and which doesn't seem to point with any clarity to a possible solution at all, let alone one with the elegance of a f = ma or e = mc2.

I suspect this book will annoy the hard-core science-is-truth crowd, but anyone with a more open mind will find a valuable perspective here.

Olly Buxton

The human mind suspended in unfathomable mystery is inevitably entangled in its webs of reason.

To illustrate: In his discussion of symmetry breaking (Chapter 4), Smolin states that "Much of the structure of the world, both social and physical, is a consequence of the requirement that the world, in its actuality, break symmetries present in the space of possibilities. An important feature of this requirement is the trade-off between symmetry and stability." However, this argument is circular: symmetries are unstable because they are broken and they're broken because they're unstable. How does the choice to break symmetries originate?

I have been reading this book on the commuter train, and it is making me look forward to my hour long commute. If you read science books for non-scientists this is one of the best I have ever read (especially if you have read the Brian Greene books, like "The Elegant Universe," because they help contextualize the author's (Lee Smolin) perception of String Theorists enthusiasm). This book is part science, and part critique of academic culture. There is also a good dose autobiographical anecdotes. Very entertaining, easy, and fun to read.

This is a mature, unbiased and informative analysis of an important aspect of science that is generally hidden from public view. It is also an enjoyable read.

Richard Feynman is usually credited having said that "philosophy of science is about as useful to scientists as ornithology is to birds." However, this book seems to indicate that, given what string theorists are doing with and for science, maybe some of them due a visit to the ornithologist...

I really enjoyed this book. Picked it up in the airport, and didn't put it down until the flight landed. Couldn't wait to get home to read more.

The author has a fantastic way of relating a technical story.

I really enjoyed this book. Picked it up in the airport, and didn't put it down until the flight landed. Couldn't wait to get home to read more.

The author has a fantastic way of relating a technical story.

This book is a MUST read for anyone who believes in the importance of science as a human endeavour.

I have read many popular books on the subjects of cosmology, particle phycics, quantum mechnanics, String theory, etc. Along the way I have read countless books that purport to be for the layman; most start strong covering the topics one would expect (wave-particle duality, the uncertainty principal, special relativity, etc.), but then quickly digress into overly technical explanations that lose most laymen. A great example is Hawking's much-touted A Brief History of Time -- I'm convinced that most people who own this book have never read the whole thing. I know I didn't.

Lee Smolin's book is a rare exception. Here is a brilliant and articulate scientist capable of describing exceptionally complex ideas in very simple terms. He understands exactly where his typical reader's limits of knowledge sit, and works carefully withing those limits. He is also sure to note when he is glossing important details that true practitioners in his field would want to elaborate on. For this alone, Smolin's book is a must-read for anyone wanting to understand the broad issues being explored in today's most advanced physics programs.

More importantly, though, this is a truly COURAGEOUS book.

Smolin states that, while it is a worthwhile endeavour, String theory has unfairly dominated major research programs for too long. For sociological and political reasons, Smolin argues that String theory has squeezed out healthy scientific debate about the "foundational" issues surrounding the unification of quantum mechanics and relativity. Smolin himself is an advocate of quantum gravity, an alternate approach to String theory. It's important to note that Smolin never claims that Loop Quantum Gravity (his favoured approach) is right; his primary point is that it is an axample of an alternate approach that it is worthy of exploration but that receives little attention.

What makes Smolin brave is that he tackles his own professional community. As anyone who has achieved some success in a field will tell you, this takes a lot of guts. And though he presents all of his arguments without malice, there is little doubt that the String theory establishment would not appreciate the way it is characterized in Smolin's book. I can only imagine the nasty response that Smolin has received (actually, there are many blogs that attack Smolin mercilessly -- when not dismissing him as a crack).

Smolin ends his books with a reflection on the general state of science in the US. He paints a bleak picture of a highly "professionalized" discipline which rewards those low-risk research programs most likely to garner large grants, and a culture where reliable technical skill is valued more than risky and innovative ideas.

Even if you disagree with Smolin's assertions (and I am sure that there are many who do), he is compelling writer with interesting things to say.

Each decade since the 60s, the leading researchers in advance physics have stepped away from their work just long enough to give us a "quick-and-dirty" status report on the latest developments in their field.

George Gamow (One, Two, Three infinity) did it at the beginning of the 60s; Gary Zukav (Wu Li Masters) did it at the end of the 70s; Heinz Pagels (Perfect Symmetry) did it at the end of the 80s; Timonthy Ferris (The Whole Shebang) did it at the end of the 90s; and now Lee Smolin's (The trouble with Physics) is doing the same for the current decade.

Never was this ride more difficult, nor clearer nor more exhilarating than as is demonstrated in the present volume. Professor Smolin takes us on a wild but sober ride across the landscape of current research in particle physics. For those of us who are frustrated physicists but whose brains are too ossified, or who no longer can read and understand the dizzying math in the technical journals, this summary is a welcomed contribution. In this panoramic view just slightly above the heads of what a layman can understand, Smolin invites us into his lab to meet his colleagues and his, and their theories.

Being a born maverick, skeptic and purest, all rolled into one, the view we get is not the normal ride of a "true believer" trying to peddle the latest "new theoretical fad," but that of a skeptic: grazing, browsing, and sampling, but in search of the "finest wares in the physics shop." Professor Smolin makes no bones about, nor does he mind us knowing, that he is from the "old school," where theories are forced to intersect with, and then be confronted by experimental results or else they are not accepted or respected as theories at all. As a "born-again" traditionalist, he is perfectly suited to give us an enjoyable guided tour.

The tour is a panoramic view of the quest for the unification of Quantum and Relativity theories into a general theory of everything (GUT), a quest, like that preceding both Relativity and Quantum Mechanics at the turn of the last Century, has again been described as the final frontier of physics: the integration of all the forces in nature to be brought together into one nice tidy theoretical coda. This quest has become the Holy Grail of the physical sciences and of Cosmology.

Exhibit 1 of this pursuit is the heavily touted "String Theory," and its progeny Super symmetry and Super string Theory, which all hit the stage with a bang, but since, as Professor Smolin so carefully demonstrates, have all run into heavy weather indeed, and which have, for the most part, now been forced to "cool their heels" and take a seat on the sidelines of traditional experimental developments.

A major part of "the trouble with physics" is what can only be called the "Kaluza-Klein cu de sac," or better yet the "Kaluza-Klein runaway train to nowhere."

Without giving away the plot of the book, the Kaluza-Klein formula proved to be a mathematically easier way to reinvent Relativity, by expanding the physics to several new dimensions. "On paper" the Kaluza-Klein derivations looked as good as Einstein's original formulation, provided of course that one is willing to overlook a few of its not so minor "fatal side effects," such as having to "roll-up' or "curl" the unwanted and untidy extra dimensions, and being willing to forego confrontations with normal experimental results.

I agreed with Professor Smolin even before I read his book: "Curling up" (or hiding) unwanted dimensions, is no way to do good physics. Yet, this unholy technique became the template that catapulted a whole generation of physicists into prominence in the world of 21st Century physics. Smolin himself admits having rode that train part way down the track until, that is, he saw the train wreck just over the horizon about to happen. When he saw it, he ever-so-discretely dismounted, leaving his "research budget fat and tenured colleagues" to endure the impending crash all by themselves. Now that he is on the safe side of the shore, where respectable experimental physics is still being done, the train is slowing down, even as it nears impact.

There does not seem to be any possibility of rescue in sight. Five stars!

Excellent review of pertinent physics and the problems with academia.
We wish more academians would open up a little more. On the other hand,
we don't want them to expose their little minds, we might cut off their funding.
Bligh

One of the most balanced and factual account of the current state of the art of Physics I have read. I wish I could get a more indepth reasoning of the unsolved problems in Physics.

Lee Smolin has written a thorough and readable book about the fact that string theory has dominated physics for more than twenty years without nailing down the Grand Unified Theory (GUT) that we all anxiously await.
His conclusion: "There needs to be an honest evaluation of the wisdom of sticking to a research program that has failed after decades to find grounding in either experimental results or precise mathematical formulation."

String theory in its various permutations became a hot topic in academic physics from around the mid-1980s, but by the end of the 1990s it had been suggested that all the conjectured and constructed string theories might be unified in a deeper (and mysterious) theory called M-theory.

According to Lee Smolin, the trouble with physics is not only that string theory may be wrong, but that its popularity has squelched innovative thinkers who wanted to take other directions within the field of physics. It became very hard for a physicist who was not interested in string theory to get a job. The academic and research communities simply did not provide jobs or grant money for physicists who disbelieved string theory or who wanted to pursue other avenues of research.

Wading through the actual physics in Smolin's book was a bit of a chore for this English major, but the history he provides is interesting and his critique of academia is clear and convincing. His overall tone is positive and upbeat in spite of the profuse apologies he keeps making to his colleagues in string theory. He ends with suggestions as to how to move the study of physics forward in ways that are more intellectually diverse than they have been in the era of string theory.

This book is not a physics entertainment, feel good, kind of book, and here's why.
Lee Smolin has tried to accurately portray the troubling issues within the field of physics these days. The physics community as a whole has seemed to have lost it's ethics or standards by which something should be promoted or studied. This is probably due to the fact that the hiring practices in the physics community is unethical, and so people with any real ethics, and a true vision, are weeded out.
The main example given in his book for an idea that has been way over promoted, is string theory. String theory -(as brought out in his book on page 352) is a theory that makes no predictions and therefore not cannot be subject to being disproved by any experiment, but nor can it be proven either. However, as stated even earlier in his book, string theory is not even a complete theory, but only a conjecture based on conjectures, that it may eventually someday contain a complete theory somewhere in all of those calculations. More probably not however.
Does he just complain? No. Professor Smolin does have the vision to at least be able to tell us in what direction we should be looking in, for a furtherance of progress. We should be asking more questions about the foundational concepts of physics. No, not all of foundational issues have been solved, just ignored. There are several assumptions about gravity, light, relativity, and quantum mechanics that have not yet been completely verified. We are indeed missing something very crucial that would allow us to make another leap forward in our understanding of the laws of our universe. This book covers these issues in detail, but it appears that the only people involved in trying to solve these worthwhile endeavors, have for the most part been put to the side by the physics community as a whole.
If we are wrong about, or don't fully understand the foundational concepts of our physics, then how can we feel that our current conjectures are sound? If the foundation is weak and incomplete, then the rest of the house is no good. If even just some of the questions regarding our foundational issues could be solved, then a seer could put some understanding to it. Do I think that the next great leap in our understanding of the laws of the universe, will answer all 5 of the great problems that Smolin has alluded too in theoretical physics? No, but it may help answer one or two of them. We're still a long long ways off from understanding how things were made, and no doubt more questions will arise to fill in for any that are eventually answered.
I give Smolin an "A" for effort, and an "A" for his candidness. String theory get's an "F", and so does the academic community. If you want the truth about string theory, and an insight into what we should be exploring in physics, then you should read this book.

I quite like this book. In fact I like it so much I recommended it to a friend of mine who has a Ph.D. in physics, and I decided to buy one for my professor in college (I studied physics as an undergrad). I cannot say I agree with all the author has to say, for example, why is he opposed to the "anthropic solution" or the "landscape of string theories" while proposing his own "cosmological natural selection"? To me, at least philosophically, the "anthropic solution" could be plausible, even though it is not testable.

That said, the most important insights I got from this book is that two main things led physics astray in recent decades: 1. over-obsession with mathematics and negligence of physical intuition or insights; 2. what the author calls "sociology". Perhaps the tenure system is the real hindrance to the advancement of science (not just physics).

I think this is a very frank book from someone "in the know" and it offers some fresh perspectives, I think anyone who thinks about pursuing a career in theoretical physics really should read it (as the author says, "theoretical physics is hard, really hard", if you are not a real genius and have extraordinary perseverance, you probably should do some more practical). For the rest of us, it is a good read nevertheless!

In his 2006 book, "The Trouble with Physics," Prof. Lee Smolin of the University of Waterloo proposes to plow up the previous 30 years of theoretical physics and reseed the ground. He claims that string theory and other adventures following the 1973 standard model of particles failed to make progress solving underlying problems. Smolin proposes five unsolved problems.

While Smolin would have readers think his views are radical, actually they are timid. Problems he poses are grand issues of philosophy. Solutions to them whould have no practical uses. Smolin continues a tradition of three generations of theoretical physicists who, unable to solve problems of practical importance, decamp to remote quarters where they hope to apply skills they already possess rather than develop new ones.

A genuinely radical approach would roll back the previous 80 years of theoretical physics, returning to the many unsolved problems of quantum mechanics from the late 1920s and developing a theory that reliably predicts from first principles commonly needed properties of matter that agree with practical measurements, including: (1) full electromagnetic emission and absorption spectra of any atom or small molecule at any ionization state, (2) collision cross-section between electrons and any atom or small molecule, (3) collision cross-sections between any atoms and small molecules, (4) structure and interaction of complex molecules, (5) structure of single-crystal solids, (6) full energy and decay spectrum of any atomic nucleus, (7) collision cross-section between free neutrons and any atomic nucleus.

There are several other such problems. A successful theory will require only four or five natural constants for scale, electromagnetism and nuclear forces and might not involve any knowledge of particle structure. A theory that solves these problems will be of signal interest for materials development, industrial chemistry, molecular biology and many other applications.

Lee Smolin has written an excellent overview of the current state of science and especially, string theory. As a layman I found his earlier chapters more valuable, as he describes in clear and easy to understand language, the history of science up to the discovery of string theory. The later chapters deal with the lack of progress in theoretical physics since the mid 1980's, and the reasons for it.
Smolin is an excellent writer and the book is easy to read. There is so much material in the book that I intend to read it a second time.

I got this book because I had read a book about string theory before. Now I don't know much about physics but this book was an interesting and easy read.

I have to say I am now completely confused - for a long time I thought the string theory is nearly ready and there are just a few tweaks to make it work. After reading this book, I realized that the string theory may be a great hoax and we are as far away from knowing how the universe works as we were in 1980's. Thank you Mr. Smolin for opening my eyes!

This book has two different parts: the first one is vibrant and, even if I did not agree with many of the author's statements, I enjoyed it. You can find some contradictions and doubtful assertions, but it is so lively and well-thought that you cannot stop reading it. You realise that, often, believing in a theory is a matter of how it is told, because I do not think that more than 0.01% of the readers are able to know if the different arguments (pros and cons) are really valid. Really worth reading.

The second part is devoted to the way science is done, and how to improve it. In my opinion, this part is very weak; the way the author justifies the success of the Copenhagen interpretation is unacceptable; the promotion of alternative theories, difficult to justify; the situation of investigation in Europe, idealized. The good thing is that this part is shorter than the first one.

While Dr. Smolin does well to point out the problems with the science community today, in my view he spends too much time on String Theory and too little on the other fields which also suffer from "entrenched" scientists. In fairness he does talk about other fields, but primarily about string theory and it gets very tiring to try to follow it, though I hung in there understanding perhaps 10-20%. My real concern is with his apparent acceptance of another fatally flawed theory - The Big Bang Theory. BBG has more flaws which have been proven by observation than String Theory, which is little more than a thought problem, since, by its very nature, it is unprovable. We simple do not have the ability at this point to verify anything on such a small scale. Just because it makes sense mathematically doesn't mean that it is real in our world. There is also no point in talking about multiple dimensions when we are incapable of seeing or detecting them. It is one thing to play with such ideas, but another altogether to claim unprovable ideas as theory or fact.

We absolutely must have these thought games and support all serious efforts to conduct research, because who knows what will come of them. Things that seemed impossible in the past became quite reasonable once all the facts were known. I believe that all of the concept of our Universe can be understood on the macro level by any reasonably intelligent person. However, understanding science on the micro level is much more difficult. It is one thing to know that water is made up of atoms of hydrogen and oxygen, and other to understand how atoms work at the subatomic level.

I've gotten pretty far afield here. I think this is a much needed book, just a bit too narrowly focused and "micro" for me. We need more such books questioning the status quo of scientific "beliefs."

A very good book; nicely written. Gives one (of the Laity) a small feeling for the beauties of high energy particle physics and the elegance of the so-called Standard Model. The book then goes on, at some length, to define and, at least partially discredit, the Next Big Thing in Science: String Theory in its multiple versions.

Judging from many of the reviews that I scanned, the book has been carefully read (and thoroughly dissected, praised and/or criticized) by persons of substantial scientific credentials. But there have also been some excellent commentaries from persons who, though not scientists, are intelligent appreciators of complex issues. I think of myself as one of these (Yes: I have read "The Elegant Universe" and "Not Even Wrong". Understood some of both.)

And yet, as important as a Demonstrable Theory of What It All Means is, I cannot see where it will change the beliefs and perceptions of millions and millions of the believers in the great religious works such as the Holy Bible or the Koran. It will NOT make any difference to the Faithful of the World's Religions.

So the concern that a Unification Theory may not put the notion of Intelligent Design to rest is, for many, many souls, not simply an issue for Physics, but--far more important--an issue for the highest, most cerebral reaches of Philosophy. This, to that huge population of Believers, is of no consequence.

To me, such a Theory would be most welcome, for I believe in science and mathematics and sweet rationality. I have the feeling after completing this excellent work, that that is not going to happen anytime soon (Something like waiting for a proof of the Riemann Hypothesis.)

Bottom Line: Give the book a try.

Naf Los Altos

This is an excellently written book, very easy to read,and with only one typo that I noticed. It starts with an excellent overview of physics from a technical point of view, without getting too technical,but a good basic understanding of physics is really needed to grasp what he is writing about, and shows the authors grasp of the technical issues, and then gets into a philosophical view of the state of physics and science generally. As an interested observer of science I have certainly noticed the lack of really big discoveries in the last twenty years or so, and this book confirms my view. Also being more of a creative thinker,rather than a conformist, a 'seer' as the author describes it,I can totally relate to the problems faced by people seeking a career in science, and the need to conform to currently popular programs and research where economic imperitives take precedence over original thinking,or even fundamental work, and where universities operate to build an image to attract students based on hype over substance. Its what put me off a career in science, and a university education, as I'm not interested in doing what others want in return for money,career,etc. The authors comment about some of the best scientists of the past being wealthy enough to support themselves in doing as they pleased is a very important point in showing that creative people are wasted if forced to do the work others want done in order to survive. Which basically leaves only those who want to conform and have an easy life and easy career path, who want to be technical experts rather than big thinkers or explorers of new concepts. It excludes most risk takers and entrepreneurs from a career in science,as you would end up bitter and unsatisfied. This book really just confirmed alot of what I thought, what should be common sense. And it makes an important point that only a few people think creatively,so it would not cost alot to employ these people and take a risk on them, in the hope that long term they will produce big things, while delivering very little of measurable worth in the short term. The book also goes into the sociology of science and scientists. Something I realised along time ago to my suprise was that scientists suffer from all the normal human flaws of bias and blindness, tribalism,etc that average people do,and often end up in religious type devoutness to their beliefs or tribe. I would have thought science would not attract such people, but it does,as the authors experience shows in confirming what I beleived just from watching science shows on TV,etc. Science would be an excellent career if not for the fact it suffers from the same B.S. that afflicts most human organisations and puts people like myself right off getting involved at all. The author is smart enough to realise that science must attract talent and compete with others for it,and his criticisms are done out of love for science and physics,not hate. It is interesting to see how carefully he treads in crisicising others, which just goes to show how religion-like science had become, and how risky it is to be a heretic, which so goes against what science should stand for,like open debate, constant questioning of all beleifs,etc, when ego's start getting in the way you might as well do something else, as its no better than any other politics or belief system. If you care about science this book raises many important points ,although I suspect it will find an audience with those that sympathise with its views and have no effect on those that need to learn from it most,as they will have closed minds and take all criticism as an attack to be defended against.A very enjoyable read.

What a superb book. Lee Smolin starts by sketching our progress towards a unified theory, and then critically examines the claims of string theory to be the best contender for that throne. Having demolished our fuzzy belief that string theory has been somehow "proven," he then weighs in on the other candidates for a unified theory, namely quantum gravity and its cousins. These turn out to be little better supported by experimental evidence. The technical concepts are clearly presented, sans equations, as developments in a story peopled with fascinating characters: the great theoretical physicists of the last 50 years. As a non-math person, I found this narrative a positive pleasure to read. In comparison to other authors of books on physics for the lay public, Smolin really knows how to tell a story, without skimping the science.

The real depth of "The Trouble With Physics" becomes apparent when Smolin pulls back to focus on physics itself. Facing the fact that the academy is a human enterprise like any other, he subjects it to the same bold criticism that he applies to scientific concepts. Here are eyeopening revelations about the culture of conferences, recommendations, networks, and above all, the economic pressures that subtly favor "craftspeople" at the expense of "seers." It's a sorry indictment of our universities, the triumph of self-interest over vision, and Smolin explicitly includes himself in the great mass of insincere careerists who choose a safe research program over a risky one, to the detriment of scientific progress. One gets the sense that this book is, for the author, an atonement for having shortchanged his own creativity as a younger man.

But we the readers are the beneficiaries of Smolin's decision to lay all bare. I have read literally dozens of books on physics and cosmology, and this is the first one that has presented the human side of the story as a CONTEXT, rather than in a series of postage-stamp portraits. Smolin shows that tribalism and rent-seeking do as much to shape science as any ideas. It is a lesson that will lend an extra savor, and a much-needed depth of perspective, to every science book I read in the future.

Lee Smolin presents a harsh critique of the last 30 years in theoretical physics, written by one of its practitioners. He makes the excellent point that science is a human activity like anything else. Progress is always hard to predict; scientists can and do get caught up in dead ends. Smolin thinks string theory is one such dead end, and makes a good case for it.

I think that, if anything, Smolin is a little too gentle on the field. The development of the atomic and hydrogen bombs left a tremendous impression that big money put into physics would bring big results. In recent years that hasn't happened. There are so many unanswered questions out there in science, so many important fields where solutions are desperately needed. When I consider the construction and operation of particle accelerators and other high-tech equipment, I can't help but think of the huge cost. The same amount of cash invested elsewhere might have brought much more in the way of useful results.

I am the mother of a 10-year-old boy attending public school. His instruction sometimes seems to me like a mishmash of well-meaning educational reforms that have been implemented with little or no testing to see if they worked or not. I am frankly disgusted by the quality of most research in the area of education--sample sizes too small, no proper controls, subjects followed for too short a time, etc. The cost of operating a single particle accelerator for six weeks probably exceeds all the funding for educational research around the world for the entire year. Yet which has the most potential for making major progress? Maybe it's time to back off on funding big physics projects for a while.

I would also like to point out that the building and use of instrumentation for high-energy physics is highly dependent on cheap fossil fuels. The future supply of such fuels is by no means guaranteed. The peak oil problem appears to be largely ignored by high-energy physicists today, but has the potential to significantly affect their ability to conduct experiments.

I really enjoyed Smolin's chapters on looking for seers rather than technicians in science. I especially liked his description of how unconventional scientists have built a career without a university job. Smolin points out that a typical professor spends a majority of his week on teaching, grant proposals, administrative tasks, and the like, leaving a surprisingly small amount of time available for actual research. Having a day job outside the field is not as big a hurdle as it might seem.

I tend to agree with Smolin that the big advances of the future are likely to come from completely unexpected directions. I can't wait to see what they are.

This book provided several discussions pf physics and quantum theory. its good because the author speaks of the history the the originators of physics theory and the current champions of thought.

I like Lee Smolin and this is a good exposition of the current quandary in Physics. When the mathematicians "hijacked" physics in the 1920's, they created ever-so elegant formulas and abstraction upon abstraction upon abstraction. "Just give me a formula!" was their mantra, and what it all really "means" was not their concern. This is the essence of Bohr's position (no pun intended), and Einstein was not able to answer, even though he knew something was missing.

String theory has many intriguing ideas, and it's supporters should not be easily dismissed. Again and again, we come back to the basic question...particle or wave? Wavicle? Partiwave? String?

At the moment, string theory appears to have many (possibly an infinite number) of "metastable vacua", each of which would allow for a universe with its own laws of physics. (For a brief, comic, yet essentially correct summary of the history of this idea, see Peter Shor's review here. For those who don't know, Shor is a celebrated quantum-information theorist.) According to the (far from established) inflationary model of cosmology, there is a vast collection of universes (the "multiverse") with diverse laws of physics. Which universe we find ourselves in is a matter of random selection, but of course we must be in a "biofriendly" universe, one whose laws of physics allow for the appearance of intelligent life.

The core argument of this book is presented on page 164-165 (US hardcover edition), where Smolin writes, "when it comes to the biofriendliness of our universe, we have at least three possibilities:

"1. Ours is one of a vast collection of universes with random laws.

"2. There was an intelligent designer.

"3. There is a so-far-unknown mechanism that will both explain the biofriendliness of our universe and make testable predictions by which it can be confirmed or falsified.

"Given that the first two possibilities are untestable in principle, it is most rational to hold out for the third possibility. Indeed, that is the only possibility we should consider as scientists, because accepting either of the first two would mean the end of our field."

I find this to be an astonishing argument. First of all, I don't know what "most rational" is supposed to mean. More importantly, to reject a scientific hypothesis for purely personal reasons (it "would mean the end of our field") is at best novel, and at worst absurd.

Very few string theorists are happy that #1 seems, at this point, to be the most likely outcome of string theory, and many hope that #3 will somehow eventually emerge. But to throw out the whole framework, simply because we don't like the result, cannot be said to be a scientific attitude.

One thing you won't learn in this book (unless you read it very carefully, and between the lines) is that the other approaches to quantum gravity advocated by Smolin have not come any closer to predicting specific experimental results than string theory has. Smolin talks about possible violations of special relativity, but these are not (as he admits on page 237) a definite prediction of loop quantum gravity. He has said (on Peter Woit's blog) that any quantum field theory in any number of dimensions is compatible with loop quantum gravity. If true, this would make loop quantum gravity even less capable than string theory of picking out our particular laws of physics.

Smolin also discusses issues of sociology in physics. On page 335-336, he asserts that the all the truly negative characterizations of job candidates that he has ever heard have had a component of racism and/or sexism. I am on the faculty of the physics department of a research university, and I can only say that my experience has been entirely different. I have simply never heard a racist or sexist denigration of one scientist by another, nor have I ever felt that anyone was being evaluated by criteria other than merit. I think that there are definitely issues of culture and how we can construct scientific communities that have broader appeal, and that there are physicists who are not as sensitive to these issues as they might be, but I cannot accept Smolin's claim that the relatively small percentage of women and blacks in physics is due to "blatant prejudice".

Finally, Smolin discusses the issues of "seers" vs "craftspeople" in science, and argues that we should be supporting more "seers". Among the existing seers, he lists some (such as Roger Penrose and Gerard 't Hooft) who made their reputations primarily as craftspeople ('t Hooft received the Nobel Prize for his work on the renormalization of gauge theories, and Penrose did celebrated work on the singularity theorems of general relativity). Their record as seers has been less successful; none of their recent ideas on modifications of quantum mechanics have panned out as yet. Smolin laments the fact that more attention is not paid to these forays into alternatives to quantum mechanics. But 't Hooft and Penrose do not agree on what modifications are needed. Other seers identified by Smolin propose violations of special relativity, rather than (or in addition to) violations of quantum mechanics. Perhaps this is all deep thought, but there is little to decide, at this point, which if any of these avenues should be pursued. Most physicists have therefore sensibly adopted a "wait and see" attitude.

Even if we accept Smolin's argument that we need new seers, how are we to find them? Smolin writes (page 353) that in order to discover "the visionaries who ignore the mainstream and follow their own ambitious programs", we should "find at least one accomplished person in the candidate's field who is deeply excited about what the candidate is trying to do". So, the candidate's program had better not be *too* far off the mainstream; there has to be at least one "accomplished person" who is "deeply excited" about it. But if one deeply excited professional is good, wouldn't more be better? Wouldn't that up the odds that the program was, indeed, worthwhile? Oh wait, that would be just what we have now ... a system where there is constant debate, emergent consensus on the most promising approaches, and distribution of research funds primarily (but by no means exclusively!) to those approaches that appear, in the consensus view, to be most promising. To paraphrase Winston Churchill on democracy, this system for distributing funds for science may be the worst ever devised, except for all the others.

So, should you buy the book? I feel that it gives a distorted picture, by emphasizing the weak points of string theory while ignoring the (many more, in my view) weak points of the alternatives. It seems to me that the essence of the book's argument against string theory is captured by the excerpts above, and by Shor's review. Then there is a lot of discussion of groupthink in scientific culture. For me, it doesn't add up to an appealing package, but your mileage may vary.

I found this book to be superbly written and full of fascinating insights. I really loved reading it. Many of the longer reviews here do a great job of reviewing the content of the book, so I'll stick to offering my opinion.

I will no doubt read this book again in the future as much of the content was way over my head. However, as with any great book on any subject, this did not prevent me from thoroughly enjoying it and learning a lot. What makes it so great is that each time I read it I will learn more.

I want to thank Lee Smolin for putting the current state of his field in some perspective. I highly, highly recommend this book!

What can I say? Like Lee Smolin, I too am a recovering mathematician, and this b