The Trouble with Physics

‘The Trouble with Physics’ by Lee Smolin is a very interesting book. Assuming I am a layman, not an expert in mathematics, and I cannot differentiate between alpha, beta, gamma and theta, and I detest pages full of formula and equations, then this book is for me. I can understand the basics of modern theoretical physics by reading this book.

It starts with the five great problems of theoretical physics, problem of quantum gravity, problem in the foundation of quantum mechanics, problem of unification of the particles and forces, problem to explain how the value of free constants in the standard model of particle physics are chosen in nature and the problem of explaining dark matter and dark energy.

He goes on to explain what he calls “The Beauty Myth”, the desire to explain various forces and phenomenon in the nature and universe through one common theory. It came in baby steps, but each attempt at unification gave rise to bigger and bigger problems for further unification of theories. The author takes us to unified-field theory, general theory of relativity and attempts to unification of gravitational and electromagnetic force. Then he briefly visits Quantum Theory and Quantum Electrodynamics (QED). We know briefly of all the discoveries made using particle accelerators. Then we know about the gauge principle, which came into being after a failed attempt to unify gravity and electro-magnetism.  The gauge principle later on led to the model of electroweak force.

Further down this brings us to supersymmetry.  Broadly this is a process in which you can replace one of the fermions ( electron, proton, neutrinos etc.) by a boson ( photon, W and Z particles etc.). Most important discovery of supersymetry is connected with the string theory.  It promised what no other theory had before, a quantum theory of gravity, at the same time a genuine unification of forces and matter. At one stroke it tried to solve at least three of the five problems of theoretical physics mentioned earlier,

The string theorists soon realized that there was now a complicated six-dimensional space and each give rise to a different version of the theory. Also in the revolution of string theories observations played no role, which is not the signature of any great discovery. String theory did not predict dark energy and even the value detected was hard for the string theory to accommodate.

The book also looks at “Physics After String Theory”. One suggestion is we have to find a way to unfreeze time, to represent time without turning it into space.  But in the end we are still searching for conclusive answers to the five problems first mentioned. Has a generation of physicists from 1970 onwards wasted all the time without making any real progress? It is for you to read, understand and come to your own conclusion.