..have passed since the beginning of strings science. The book presents the recent state of mathematical calculations and related speculations about strings, branes and extra dimensions. I truly find hard time to rate this brave and appreciated attempt by the author. Is it well written? - yes. Is it interesting? - not that much.

The main point is that we are still in the dark, nothing concrete about new developments. The more calculations, the more questions. Reader will encounter numerous new definitions and nomenclature: relativistic strings, worldsheet string theory, M-theory, IIA/IIB-theories, T- dualities, gauge/string dualitiy, superstrings, supergravity, D-branes, solitonic branes,"gauge"-measurements and symmetry, bosonic and fermionic dimensions, just to mention a few. Almost every chapter contains assurance: "this or that" is not well understood or mysterious.

Yet..I finished reading this book. IMO it is a good text for college students who would like to study mathematics and particle physics. Or..it is for absolutely crazy about science and cosmology people, like myself. If you are not one of them, skip it.