Thermal Tachyacoustic Cosmology

  title={Thermal Tachyacoustic Cosmology},
  author={Abhineet Agarwal and Niayesh Afshordi},
  journal={Physical Review D},
Perimeter Institute for Theoretical Physics, 31 Caroline St. N., Waterloo, ON, N2L 2Y5, Canada(Dated: June 5, 2014)An intriguing possibility that can address pathologies in both early universe cosmology (i.e. thehorizon problem) and quantum gravity (i.e. non-renormalizability), is that particles at very highenergies and/or temperatures could propagate arbitrarily fast. A concrete realization of this pos-sibility for the early universe is the Tachyacoustic (or Speedy Sound) cosmology, which… 

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