Bouncing Universes in String-inspired Gravity

نویسندگان

  • Tirthabir Biswas
  • Anupam Mazumdar
  • Warren Siegel
چکیده

We consider the effects on cosmology of higher-derivative modifications of (effective) gravity that make it asymptotically free without introducing ghosts. The weakening of gravity at short distances allows pressure to prevent the singularity, producing a solution with contraction preceding expansion.

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تاریخ انتشار 2008