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arXiv · hep-th/0105206

\$tring Theory and an Accelerating Universe

John Ellis·N. E. Mavromatos·D. V. Nanopoulos
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Abstract

An accelerating Universe can be accommodated naturally within non-critical string theory, in which scattering is described by a superscattering matrix \$ that does not factorize as a product of $S$- and $S^\dagger$-matrix elements and time evolution is described by a modified Liouville equation characteristic of open quantum-mechanical systems. We describe briefly alternative representations in terms of the stochastic Ito and Fokker-Planck equations. The link between the vacuum energy and the departure from criticality is stressed. We give an explicit example in which non-marginal \$tring couplings cause a departure from criticality, and the corresponding cosmological vacuum energy relaxes to zero à la quintessence.

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John Ellis, N. E. Mavromatos, D. V. Nanopoulos. 2001-05-21. \$tring Theory and an Accelerating Universe. https://arxiv.org/abs/hep-th/0105206

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