Agravity

Title:  Agravity

Presenter:  Alberto Salvio (IFT-UAM)

Abstract:  We will explore the possibility that the fundamental theory of nature does not contain any scale. This implies a renormalizable quantum gravity, which can be reinterpreted as a graviton minus an anti-graviton (agravity). We will show the super-Planckian renormalization group equations of gravity coupled to a generic matter sector. The Planck scale and a flat space can arise dynamically at quantum level provided that the quartic coupling of a scalar, which we call the Higgs of gravity, and its β function vanish at the Planck scale; for example, this is how the Higgs boson behaves for a Higgs mass Mh ≃ 125GeV and a top mass Mt ≃ 171GeV. We will also discuss the implementation of this general idea in specific models and discuss possible dark matter candidates. Within agravity, inflation is a generic phenomenon: the slow-roll parameters are given by the β-functions of the theory, and are small if couplings are perturbative. If the inflaton is identified with the Higgs of gravity the predictions for the scalar spectral index ns ≃0.967 and the tensor-to-scalar ratio r ≃ 0.13 arise. Furthermore, a small weak scale can be natural and is generated by agravity quantum corrections.