PIRSA:17040006

Cosmological Variations

Kaplan, D. (2017). Cosmological Variations. Perimeter Institute. https://pirsa.org/17040006

Kaplan, David. Cosmological Variations. Perimeter Institute, Apr. 12, 2017, https://pirsa.org/17040006 

          @misc{ pirsa_PIRSA:17040006,
            doi = {10.48660/17040006},
            url = {https://pirsa.org/17040006},
            author = {Kaplan, David},
            keywords = {Other},
            language = {en},
            title = {Cosmological Variations},
            publisher = {Perimeter Institute},
            year = {2017},
            month = {apr},
            note = {PIRSA:17040006 see, \url{https://pirsa.org}}
          }

David E. Kaplan Johns Hopkins University - Department of Physics & Astronomy

DOI 10.48660/17040006
Collection
Talk Type Scientific Series
Subject

Abstract

I present three possible non-standard additions to cosmology.  First I show that a very long early period of inflation could exist in which parameters evolve, or 'relax', to seemingly fine-tuned values.  Next, I show that even if cosmic inflation existed, a period after inflation with anisotropic stress can dramatically affect super-horizon modes and thus the imprint on the cosmic microwave background.  Finally, I show that cosmological singularities can be avoided by a bounce without using exotic matter that violates the Null Energy Condition, but by the addition of vorticity in compact extra dimensions.