This is the second edition, with changes and additions, of a book proposed about two years ago. For the layman, modern physics is like an immense and magnificent cathedral that is impressive in its complex and sophisticated architecture, and amazing in size and richness of the workmanship. Yet, in this apparently almost complete edifice, there is no answer to a long series of basic and crucial questions, while in any case these answers are indispensable and preliminary to any general theory. It is essential to avoid the confusion between appropriate and clarifying answers and false tautological answers or formulas that actually say nothing about the questions posed. In this book, the starting point is the interpretation given by Einstein’s general relativity to explain the gravitational force not as an action at a distance but as an effect intrinsic to the deformation of space caused by a “mass”. This interpretation is extended to the explanation of any attractive or repulsive force as an effect of flattening of dimensions with positive or negative curvature, one for each force. It offers, without any forcing, an explanation for most of the unsolved questions of physics, of the nature of a mass, matter and antimatter, of the structure of an atom, of the origin of natural constants, of the quantization of phenomena, etc. It also offers a different interpretation of the nature of electrons and black holes. Furthermore, the existence of antimatter in protons, but not in neutrons, is also predicted, a phenomenon that appears to be documented by recent works. This book is not written by a physicist but it is also highlighted why a professional physicist would have to overcome serious or insurmountable difficulties to give innovative answers to the fundamental unsolved problems of physics using concepts unrelated to those currently accepted.