UV-complete relativistic field theories and softened gravity

          @misc{ pirsa_PIRSA:18060015,
            doi = {10.48660/18060015},
            url = {https://pirsa.org/18060015},
            author = {Salvio, Alberto},
            keywords = {Cosmology, Particle Physics},
            language = {en},
            title = {UV-complete relativistic field theories and softened gravity},
            publisher = {Perimeter Institute},
            year = {2018},
            month = {jun},
            note = {PIRSA:18060015 see, \url{https://pirsa.org}}
          }
          

Abstract

A field theory is fundamental if it features a UV fixed point (either trivial or interacting). Gravity may not change drastically the UV behavior if the Einstein gravitational interactions are softened above a critical sub-Planckian energy scale. A concrete implementation of this softened gravity can be obtained by adding terms quadratic in the curvature to the Einstein-Hilbert action. One way to implement this scenario consists in requiring that all matter couplings flow to zero at infinite energy (total asymptotic freedom). More generally, some of the couplings flow to zero, while others approach interacting fixed points. The requirement of having a fundamental field theory can have important implications for particle physics phenomenology.