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Universal Approach to Cosmological Singularities in Two Dimensional Dilaton Gravity

G. N. Martin·F. D. Mazzitelli
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Abstract

We show that in a large class of two dimensional models with conformal matter fields, the semiclassical cosmological solutions have a weak coupling singularity if the classical matter content is below a certain threshold. This threshold and the approach to the singularity are model-independent. When the matter fields are not conformally invariant, the singularity persists if the quantum state is the vacuum near the singularity, and could dissappear for other quantum states.

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G. N. Martin, F. D. Mazzitelli. 1994-04-18. Universal Approach to Cosmological Singularities in Two Dimensional Dilaton Gravity. https://doi.org/10.1103/physrevd.50.r613

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