This is a book I wish I would have read back in 2006 when it was published. It gives a mathematical physicist's argument against string theory. Woit has a blog started in 2004 under the same name as this book. It discusses theoretical particle physics and mathematics and in particular is an ongoing criticism of string theory, multiverses and other theories that make no connection to observables and that can never be falsified. The level of this book is the same as the blog, very readable.

The book gives a historical development of particle physics theory starting with the development of quantum mechanics in the 1920's and leading up to the culmination of the standard model of particle physics. Then as the author states throughout the book "The discovery of the standard model is an intellectual achievement that will be remembered for the rest of human history. One unexpected result of this progress has been that the field of theoretical particle physics has now been a victim of its own success for nearly a quarter century". To this date (2014) there has not been any experimental result in particle physics that cannot be described by the standard model. However, there are known problems with the Standard model. Problems such as unifying the electroweak force with the strong force and explaining the values of twenty or so adjustable parameters in the standard model. Many model and theories were developed along the way to the standard model one of them being string theory.

String Theory developed in the 70's was originally proposed to try and understand the strong force. Over time hope began to grow that it could describe all the known particles and the four known forces. It became of "Theory of Everything". One big problem, it couldn't calculate anything to compare to experiment. The hope to relate it to experimental data was always over the next horizon waiting for the next big insight. This situation has been going on now for thirty years or so with the author saying that string theory has been a drag on resources that otherwise could be used on working on other theories. The author takes a similar view to what Lee Smolin discusses in his book "The Trouble with Physics". In the world of folks opposed to string theory Woit's book and Smolin's book work together very well. Both give compelling arguments against string theory and the negative effect it has had on physics in general. The author discusses in a field with limited resources how string theory has negatively effected the entire physics community. However Woit being a mathematical physicist does say how string theory and certain areas of mathematics have grown together partly due to the string theorist Ed Witten. This is a tread throughout the book in how over the past hundred years or so how physics and mathematics have helped one another in certain areas. This to me made interesting reading when he discusses the collaborative efforts between the two disciplines.

Woit's account stresses the use of group theory in quantum mechanics especially the influence of Herman Weyl. Various ideas in group theory are described very well such as describing what is a group what is a Lie group and why group theory is useful in physics. He discusses what is an SU(3) group for example. I wish he would have used equations and examples but that is not the purpose of this book. The level of discussion is that of what you would read in a Scientific American article.

I thoroughly enjoyed this book and would recommend it to anyone interested in particle physics, its relationship with mathematics and to understand why there is disagreement in the physics world about string theory and the negative effect it has had.on science.

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