This is a booklet that fulfills several functions at the same time. It is an outline of the personal path that Carlo Rovelli has followed into the strange world of fundamental physics. He provides a fascinating insight into how personal factors also play a role, such as chance encounters, inspiring or actually curbing cultural and organizational factors, the fierce battle for the funding of research projects, and so on. And it is a nice plea for fundamental scientific research, which is critical and rational, but also modest and admits that it can be mistaken.

But at the same time this book is also apologetic: Rovelli emphatically defends his own approach in physics, that of 'loop theory' that focuses on quantum gravity and that states that micro-space consists of a finite number of infinitely complex interconnected loops. That loop theory is a competitor of the more well-known and still more followed "string theory" (which is more based on quantum mechanics), but Rovelli firmly supports his approach. Obviously I am not in a position to judge that choice, but at least Rovelli presents the battle in a way that is reasonably understandable to a layperson, and that is quite an achievement! The fact that loop theory implies that notions such as time and space at the absolute micro level (of atoms and protons, for example) are irrelevant, remains a difficult nut to crack for a layman. See also my review in my Sense-of-History account: https://www.goodreads.com/review/show/2895266236 ( )

http://www.direnzo.it/main.phtml?Language=it&Doc=0001&ISBN=8883230825 ( )