Weyl Curvature Hypothesis in Light of Quantum Backreaction at Cosmological Singularities or Bounces

  title={Weyl Curvature Hypothesis in Light of Quantum Backreaction at Cosmological Singularities or Bounces},
  author={Bei-Lok Hu},
  • B. Hu
  • Published 3 October 2021
  • Physics
  • Universe
The Weyl curvature constitutes the radiative sector of the Riemann curvature tensor and gives a measure of the anisotropy and inhomogeneities of spacetime. Penrose’s 1979 Weyl curvature hypothesis (WCH) assumes that the universe began at a very low gravitational entropy state, corresponding to zero Weyl curvature, namely, the Friedmann–Lemaître–Robertson–Walker (FLRW) universe. This is a simple assumption with far-reaching implications. In classical general relativity, Belinsky, Khalatnikov and… 

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