Cosmological singularities in Bakry-Émery spacetimes

  title={Cosmological singularities in Bakry-{\'E}mery spacetimes},
  author={Gregory J. Galloway and Eric Woolgar},
  journal={Journal of Geometry and Physics},
Abstract We consider spacetimes consisting of a manifold with Lorentzian metric and a weight function or scalar field. These spacetimes admit a Bakry–Emery–Ricci tensor which is a natural generalization of the Ricci tensor. We impose an energy condition on the Bakry–Emery–Ricci tensor and obtain singularity theorems of a cosmological type, both for zero and for positive cosmological constant. That is, we find conditions under which every timelike geodesic is incomplete. These conditions are… Expand
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