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arXiv · hep-th/9206078

A Closed, Expanding Universe in String Theory

Chiara R. Nappi·Edward Witten
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Abstract

We present a conformal field theory -- obtained from a gauged WZW model -- that describes a closed, inhomogeneous expanding and recollapsing universe in $3+1$ dimensions. A possible violation of cosmic censorship is avoided because the universe recollapses just when a naked singularity was about to form. The model has been chosen to have $c=4$ (or $\widehat c=4$ in the supersymmetric case), just like four dimensional Minkowski space.

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Chiara R. Nappi, Edward Witten. 1992-06-19. A Closed, Expanding Universe in String Theory. https://doi.org/10.1016/0370-2693(92)90888-b

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