KeywordsFundamental interactions, gravity, Higher-spin gravity, gauge theories, String Theory
The general framework of this project is the (very ambitious) problem of quantizing gravity. Einstein’s General Relativity is very efficient when describing gravitational interactions at the scale of the solar system, but at larger and smaller scales, many puzzles arise. In particular, it is believed that quantum effects of gravity have to be accounted for at the core of black holes, though no consistent theory of quantum gravity exists. Black Holes are not only fascinating theoretical objects, they are also observed in most of the galaxies and have recently been observed directly, via the emission of gravitational waves. String Theory has provided many clues towards a quantum theory of gravity, but still is in infancy. The line of attack to the problem of quantizing gravity that we have been proposing in the research unit Mechanics and Gravitation since 2009 is called Higher-Spin Gravity. In this framework, infinitely many gauge fields with unbounded spin are added to the graviton in a way compatible with a infinite-dimensional gauge symmetry algebra. We propose to analyse various issues in Higher-Spin gravity, with the aim of shedding some light on a maximally symmetric phase of String Theory.