The book is essentially a critique of string theory, although that really only provides a framework for a broader and deeper discussion of the state of physics and science, the philosophy of science and problems in the academia. Smolins writing is enjoyable and I kept nodding by myself enthusiastically through most of the book. However, at times it may feel that the themes of the book are not quite connected, or they are discussed only superficially. Smolin does not go into much detail about some of the relevant background in physics, such as gauge theories, so unless the reader is already familiar with much of contemporary physics it can sometimes seem that too much is assumed. Having said that, Smolin makes it incredibly easy to grasp the major problems of contemporary physics (he lists five of them: the problem of quantum gravity, the foundations of quantum mechanics, the unification of particles and forces, the fixing of the values of the free constants in the standard model, and the nature of dark matter and dark energy). All in all the only flaw in the book to my mind is that it couldve been longer and gone into more detail on some of the issues. Smolin does have other books which do just that though, such as his 1997 book The Life of the Cosmos, which I quite fancy reading now.Much of Smolins discussion of string theory focuses on a simple theme: because string theory has failed to make any empirically testable predictions and is hence not falsifiable, at least not in the usual sense, it does not deserve the dominant position that it currently has in theoretical physics. Indeed, it is not even a particularly well formulated theory. Smolin discusses the scientific, historical and sociological causes for the current state of theoretical physics in which it seems that the only viable career choice is to engage in research concerning one of the currently fashionable problems in string theory. This discussion is fascinating in that it gives an insiders look into the everyday work of theoretical physicists it is remarkable how many similarities one can find between Smolins description of the less admirable aspects of the endeavours of theoretical physicists and those of philosophers.Philosophers may find Smolins discussion of the philosophy of science rather superficial, but one must keep in mind that the book is written for the layman who lacks philosophical education. Besides, it is clear that Smolin himself does have a good grasp of the relevant issues, although his discussion of the work of Popper for instance may lack the input of more recent work in the philosophy of science. Still, Smolin actually met Feyerabend several times and he has some funny anecdotes to share.Although Smolins discussion of contemporary physics and string theory in particular are extremely interesting, I thought, rather surprisingly, that the best aspect of the book is the discussion concerning the sociological aspects of science. Some of this discussion, such as Smolins application of the so called group think idea to the behaviour of the string theory community is perhaps a bit too simplified, but I have no doubt that there is an element of truth to it. Smolin also seems to be particularly concerned about the prospects of young researchers and about the fact that they are not being encouraged to think for themselves and to pursue risky, original research projects. Rather, if one wishes to embark on a successful career in theoretical physics, it seems that jumping right into some fashionable aspect of the dominant field, i.e., string theory, is the only way to go. It strikes me that the situation, although certainly not as drastic as it seems to be in theoretical physics, is rather similar in philosophy: it is extremely difficult to sell a research project which deviates from accepted philosophical dogmas. I think that the Quinean conception of ontological commitment is a good example of such a dogma which is all the more ironic given that Quines best known paper was entitled Two Dogmas of Empiricism! Let me quote a passage from Smolin concerning research ethics which I think is probably descriptive of much of academia (p. 306):"Adherence to the shared ethic is never perfect, so there is always room for improvement in the practice of science. This seems especially true today, when fashion appears to be playing too large a role, at least in physics. You know this is happening whenever there are bright young PhDs who tell you privately that they would rather be doing X but are doing Y because that is the direction or technique championed by powerful older people, and they thus feel the need to do Y to get funding or a job. Of course, in science as in other areas, there are always a few who choose to do X in spite of the clear evidence that the doers of Y are better rewarded in the short term. Among them are the people who will most likely lead the next generation. Thus the progress of science may be slowed by orthodoxy and fashion, but as long as there is room for those who do X instead of Y, it cannot be stopped completely."Smolins greatest concern is the relative lack of room for those who choose to do X. I share that concern, perhaps because I happen to be doing something like X myself! In any case, the real lesson of The Trouble with Physics is that we should not become bogged down with a fashionable approach to a certain problem, even if it seems to enjoy wide support. Thats not how science (or philosophy) works; we need to have several parallel lines of research while knowing full well that only one of them may be correct. The problem is that we can never be certain which one of them it is more often than not the correct line of research has turned out not to be the most popular one.

It is well known now, that a very large cadre of talent in theoretical physics has been working on string theory. The theory solves a lot of problems in physics, and Lee theoretical physicist Lee Smolin has published a number of papers on the subject. The problem is that, the theory does not make any predictions that might allow it to be "falsifiable". So, according to my definition of a theory--a scientific idea that is supported by much observational evidence from a number of different approaches--string theory is not a theory at all. It is a hypothesis that has yet to be upheld by observational evidence. And, in the three decades preceding this book, Smolin writes that no fundamental discoveries had been made in physics--a sudden stoppage in progress that had been flowing since the early 1900's. And, when presented with this problem, string theorists are simply certain that their approach is correct; they are even willing to change the philosophical definition of what is science, by suggesting that science requires a new paradigm that does not require confirmation by observational evidence.This book begins by reviewing the landscape of physics before the rise of string theory, and then goes into some detail about string theory itself. Then the book describes the successes and shortcomings of string theory, and the alternative theories/hypotheses that have been proposed.But this book is as much about the sociology of physicists, as it is about science. To me, this is quite interesting, as Lee Smolin is not subtle in his discussion about the physics community. And, Smolin is quick to admit that he is as guilty as others, in his inability to make progress. He had been working in quantum gravity, and"felt like the high school dropout invited to watch his sister graduate from Harvard with simultaneous degrees in medicine, neurobiology, and the history of dance in ancient India.Now, this book was published in 2006, and I am told that the situation has changed somewhat since then, especially with the new discoveries being made by the LHC (Large Hadron Collider) at CERN. However, Smolin documents some very disturbing tendencies that are still alive in physics, and in science in general. Smolin asserts that these tendencies are very close to a phenomenon called "groupthink", where everyone in a community is pressured to think in the same way.Smolin writes that there are two types of scientists; craftsmen and seers. The craftsmen are very clever and have excellent technical skills. They have a tendency to work on what Smolin calls "normal science", that is, to follow the fashionable trends. They generate incremental progress in science through hard work. The problem is that they are not going to produce a "revolution" in science. The "seers", on the other hand, are visionaries. They are willing to question the fundamental assumptions that underlie physics. They do not necessarily have strong technical skills, but they are visionaries, and are not willing to "follow the crowd".It is ironic that the scientists who first developed string theory were themselves scientific pariahs for many years. They worked on the fringes of the physics community, and their ideas were not welcomed. They could not obtain academic positions. After more than a decade, their ideas started to get noticed, up to the point where string theory became mainstream. Now, it is the physicists who do not research in string theory who are the pariahs. And according to Joanne Hewett, "... the arrogance of some string theorists [is] astounding, even by physicists' standards. Some truly believe that all non-stringy theorists are inferior scientists. It's all over their letters of recommendation for each other ..."Smolin writes that science needs both the craftsmen and the seers, but only the craftsmen can have normal careers in the present system. Only when young PhD's pursue research along the lines of the older generation, can they have a hope of advancing to a postdoc position, gain funding, and ultimately obtain a professor position. Today, that is how the system works.Much of the physics that Smolin writes is over my head--it is difficult for someone not already steeped in theoretical physics to follow very closely. But I was fascinated by a discovery known as "Milgrom's law" in the 1980s. The discovery has to do with where the gravitational acceleration of galaxies breaks down--it breaks down at 1.2x10^-8 cm/sec^2, which is precisely c^2/R, where R is the scale of the curvature of the universe. Physicists invented the concept of "dark matter" to explain this break-down, so question is whether this match in acceleration is simply a coincidence, or a sign of something more fundamental at work.Smolin is a distinguished researcher, and his descriptions of the science are authoritative. Some discussions I've had with physicists corroborate much of what Smolin writes about the sociology of string theorists. This is an important book, not only about academic physics, but about how all sciences are conducted.

It is very hard in writing a popular book about physics to strike the right balance between rigorous explanation and appeal to a broad audience. From the favorable Goodreads reviews, it is evident that a lot of people think that Smolin has struck the right balance here, but not for me. There is just too much hand waving in this book for my taste. He trots out scientists and their theories like characters in an Andrew Lloyd Weber musical -- "Hi, I'm a Jellicle Cat, and this is what I do, dum, dee, dum, dum." It is a pretty song, and I learn a couple of things about the character, but in the end, I still don't really understand what the heck a Jellicle Cat is. I would have liked the book a lot better, if Smolin had covered less ground and had given more background for the science. As it was written, I wanted to agree with the analysis and the basic philosophical point of view, but I didn't feel that I had been given enough grounding in the science to be able to fairly reach a conclusion and was left with having to rely on Smolin's word as an expert, a predicament that Smolin himself identifies and decries among the string theorists, but does not seem to see as well in the position in which he puts his own readers.

Wow. This is an important work for anyone interested or concerned with the current state of science and funding. Beyond the fact that I learned more about theoretical physics and string theory here than any other pop-sci book before, I couldn't get enough of this one. I'll never be able to grasp the hardcore numbers involved in physics of this scope, but I can appreciate the theories and ideas involved. Smolin did a better job explaining it to me than anyone I've read before, and he doesn't even agree with their theory. I've long known that science funding and research has gotten more and more fuddled up with bias for the in vogue ideas in whatever field one is trying to research, but this book made me realize how much worse it actually is than I had even realized. It made me quite sad tbh, but I'm really glad I read it. I hope that the work Smolin and others are doing to remedy the situation comes about sooner rather than later, so we can advance further as a species in our understanding of the universe and how it works.

I really liked this book. I've been curious for years about what all the fuss was about, regarding string theory. I've watched a few shows on TV that had string theorists that tried to explain it, like Brian Greene, but they always seemed to just talk around it with flowery language, never explaining the nuts and bolts of how exactly it was the "theory of everything". Lee Smolin does a good job of showing that the emperor has no clothes. If he is correct, and his writing has that "ring of truth", string theory has been a decade-plus big complex mathematical exercise, and nothing more. But the main focus of his book isn't that string theory has failed (still too early to say that for sure I guess), but rather criticizing how it has monopolized theoretical physics in terms of grants, post-doc positions, etc., and the arrogance of string theorists, and how that's bad for science. But the most important point he makes is that string theory has never made any testable predictions, and that some string theorists are even saying maybe we should redefine "science" so that it doesn't have to be testable! Talk about arrogance there, these guys' favorite theory is turning into a hairball, they can't test it or falsify it (or prove it correct), so instead of admitting that maybe they are on the wrong track and should try something else, they want to redefine what science is. Saying stuff like that should be grounds for having your tenure revoked. He argues (rightfully IMO) that we need more of a balance in supporting different competing theories because it's way too early to decide which is on the right track. It's probable that none of the existing theories is the "right one".Very good book about how science can go wrong sometimes, because it's driven by people and organizations, which are never perfect. But science is unique in that it eventually self-corrects, it just takes longer than it should sometimes.