Inflation with a Cutoff: Proposals and Problems

          @misc{ scivideos_PIRSA:07110039,
            doi = {10.48660/07110039},
            url = {https://pirsa.org/07110039},
            author = {Niemeyer, Jens},
            keywords = {Quantum Gravity},
            language = {en},
            title = {Inflation with a Cutoff: Proposals and Problems},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2007},
            month = {nov},
            note = {PIRSA:07110039 see, \url{https://scivideos.org/pirsa/07110039}}
          }
          

Abstract

The possible existence of a physical UV cutoff in dynamical spacetimes raises a number of conceptual and practical questions. If the validity of Lorentz Invariance is considered unreliable above the cutoff, the creation or destruction of quantum modes and the choice of their initial state need to be described explicitly. It has been proposed that these trans-Planckian effects might leave an oscillatory imprint on the power spectrum of inflationary perturbations. However, taking into account the fluctuations of the cutoff, the signal is smeared out beyond recognition.