The Vacuum Energy Problem in Quantum Gravity and the Masses of Elementary Particles

Abstract: This talk summarizes a new understanding of the cosmological constant problem, which essentially relies on a phase-space-like computation of the vacuum energy, both in the realm of quantum field theory coupled to gravity, and in the realm of a consistent formulation of a quantum theory of gravity and matter, such as string theory, combined with central properties of gravitational entropy as captured by the Bekenstein bound. This new understanding of the vacuum in a quantum theory of gravity and matter sheds light on the Higgs mass as well as the masses of quarks and leptons.