A Simple Harmonic Universe

          @misc{ scivideos_PIRSA:11070021,
            doi = {10.48660/11070021},
            url = {https://pirsa.org/11070021},
            author = {},
            keywords = {Cosmology},
            language = {en},
            title = {A Simple Harmonic Universe},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2011},
            month = {jul},
            note = {PIRSA:11070021 see, \url{https://scivideos.org/index.php/pirsa/11070021}}
          }
          

Abstract

We explore simple but novel solutions of general relativity which, classically, approximate cosmologies cycling through an infinite set of ``bounces." These solutions require curvature K=+1, and are supported by a negative cosmological term and matter with -1 < w < -1/3. They can be studied within the regime of validity of general relativity. We argue that quantum mechanically, particle production leads eventually to a departure from the regime of validity of semiclassical general relativity, likely yielding a singular crunch.