Antigravity and the big crunch/big bang transition

@article{Bars2012AntigravityAT,
  title={Antigravity and the big crunch/big bang transition},
  author={Itzhak Bars and Shih-Hung Chen and Paul J. Steinhardt and Neil Turok},
  journal={Physics Letters B},
  year={2012},
  volume={715},
  pages={278-281}
}
Abstract We point out a new phenomenon which seems to be generic in 4d effective theories of scalar fields coupled to Einstein gravity, when applied to cosmology. A lift of such theories to a Weyl-invariant extension allows one to define classical evolution through cosmological singularities unambiguously, and hence construct geodesically complete background spacetimes. An attractor mechanism ensures that, at the level of the effective theory, generic solutions undergo a big crunch/big bang… Expand

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