Book review: Covariant Loop Quantum Gravity, an elementary introduction to quantum gravity and spinfoam theory

Rodolfo Gambini is Professor of Physics at Universidad de la República, Montevideo Uruguay

Rodolfo Gambini is Professor of Physics at Universidad de la República, Montevideo Uruguay

Review of “Covariant Loop Quantum Gravity, an elementary introduction to quantum gravity and spinfoam theory” by Carlo Rovelli and Francesca Vidotto

One of the central problems of contemporary physics is finding a theory that allows for describing the quantum behavior of the gravitational field. This book is a remarkable update on one of the most promising approaches for the treatment of this problem: loop quantum gravity. It places special emphasis on the covariant techniques, which provide with a definition of the path integral, an approach known as spin foams. It is a field that has undergone quite a bit of development in the last two decades. The book gives an overview of this area, discussing a series of results that are presented with great clarity. Both students and established researchers will benefit from the book, which provides a dependable introduction and reference material for further studies. Only a basic knowledge of general relativity, quantum mechanics and quantum field theory is assumed. The conceptual aspects and key ideas are discussed in the main body of the book and Continue reading

Designing curved blocks of quantum space-time…Or how to build quantum geometry from curved tetrahedra in loop quantum gravity

Etera Livine

Etera Livine is a CNRS researcher and focuses especially on mathematical aspects of loop quantum gravity and spinfoam path integral models. Etera and Christoph both work on quantum gravity at the Laboratoire de Physique de l’Ecole Normale Supérieure de Lyon (LPENSL) in France.

Among the various approaches to the quantum gravity challenge, loop quantum gravity proposes a framework for a canonical quantization of general relativity, describing how the 3d geometry evolves in time. It does not require a priori extra dimensions or supersymmetry. It defines spin network states for the quantum geometry directly at the Planck scale, with a discrete spectra of areas and volumes, and computes their transition amplitudes by path integrals inspired from topological field theory, called spinfoam models. This framework is mathematically rigorous but Continue reading