Sailing through the big crunch-big bang transition

  title={Sailing through the big crunch-big bang transition},
  author={Itzhak Bars and Paul J. Steinhardt and Neil Turok},
  journal={Physical Review D},
In a recent series of papers, we have shown that theories with scalar fields coupled to gravity (e.g., the standard model) can be lifted to a Weyl-invariant equivalent theory in which it is possible to unambiguously trace the classical cosmological evolution through the transition from big crunch to big bang. The key was identifying a sufficient number of finite, Weyl-invariant conserved quantities to uniquely match the fundamental cosmological degrees of freedom across the transition. In doing… 

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