Comments on Cosmological Singularities in String Theory

@article{Berkooz2002CommentsOC,
  title={Comments on Cosmological Singularities in String Theory},
  author={Micha Berkooz and Ben Craps and David Kutasov and Govindan Rajesh},
  journal={arXiv: High Energy Physics - Theory},
  year={2002}
}
We compute string scattering amplitudes in an orbifold of Minkowski space by a boost, and show how certain divergences in the four point function are associated with graviton exchange near the singularity. These divergences reflect large tree-level backreaction of the gravitational field. Near the singularity, all excitations behave like massless fields on a 1+1 dimensional cylinder. For excitations that are chiral near the singularity, we show that divergences are avoided and that the… Expand
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