2013/12/31 by Itzhak Bars, Paul J. Steinhardt, Paul Steinhardt +1 · 1 citation
Mathematics · Physics and Astronomy · #Astrophysics #Big Bang (financial markets) #Big Bounce #Big Crunch #Black Holes and Theoretical Physics #Cosmology #Cosmology and Gravitation Theories #Crunch #Dark energy #De Sitter universe #Economics #Finance #Galaxies: Formation, Evolution, Phenomena #Geodesic #Invariant (physics) #Lambda-CDM model #Mathematical analysis #Mathematical physics #Mathematics #Physical cosmology #Physics #Theoretical physics #Ultimate fate of the universe #Universe #astro-ph.CO #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.89.061302
published as Phys. Rev. D 89, 061302 (2014) · 3 pages, 1 figure. In version v2 the last three paragraphs include a response to the Note added to Ref. 18
arxiv created 2014/02/01 · openalex publication_date 2014/03/05 · arxiv updated 2014/03/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
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 so we had to account for the well-known fact that many Weyl-invariant quantities diverge at the crunch and bang. Recently, some authors rediscovered a few of these divergences and concluded based on their existence alone that the theories cannot be geodesically complete. In this paper, we show that this conclusion is invalid. Using conserved quantities we explicitly construct the complete set of geodesics and show that they pass continuously through the big crunch-big bang transition.