The Challenging Cosmic Singularity

Hong Liu; Gregory Moore; Nathan Seiberg

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The Challenging Cosmic Singularity

Hong Liu·Gregory Moore·Nathan Seiberg

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Abstract

In this talk we discuss the cosmic singularity. We motivate the need to correct general relativity in the study of singularities, and mention the kind of corrections provided by string theory. We review how string theory resolves time-like singularities with two examples. Then, a simple toy model with lightlike singularities is presented, and studied in classical string theory. It turns out that classical string theory cannot resolve these singularities, and therefore better understanding of the full quantum theory is needed. The implications of this result for the Ekpyrotic/Cyclic Model are discussed. We end by mentioning the known suggestions for explaining the cosmological singularity.

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Hong Liu, Gregory Moore, Nathan Seiberg. 2002-12-31. The Challenging Cosmic Singularity. https://arxiv.org/abs/gr-qc/0301001

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