String Propagation in the Presence of Cosmological Singularities

  title={String Propagation in the Presence of Cosmological Singularities},
  author={Ben Craps and David Kutasov and Govindan Rajesh},
  journal={Journal of High Energy Physics},
We study string propagation in a spacetime with positive cosmological constant, which includes a circle whose radius approaches a finite value as |t|??, and goes to zero at t = 0. Near this cosmological singularity, the spacetime looks like 1,1/. In string theory, this spacetime must be extended by including four additional regions, two of which are compact. The other two introduce new asymptotic regions, corresponding to early and late times, respectively. States of quantum fields in this… 

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