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Closed String Tachyon Condensation and Worldsheet Inflation

Bruno Carneiro da Cunha·Emil J. Martinec
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Abstract

Closed string tachyon condensation in spacetime generates potentials on the worldsheet that model two-dimensional inflationary cosmology. These models illustrate and elucidate a variety of aspects of inflation, in particular the generation of quantum fluctuations and their back-reaction on geometry. We exhibit a class of Liouville gravity models coupled to matter that can exhibit, for example: (a) pure de Sitter gravity; (b) slow-roll inflation; (c) topological inflation; and (d) graceful exit into an FRW phase. The models also provide a quantitative testing ground for ideas about the origin of inflation, such as the various `no-boundary/tunnelling' proposals, and the `eternal/chaotic' inflationary scenario. We suggest an alternative mechanism for quantum creation of cosmological spacetimes which, in the context of the model, provides a natural explanation for why the typical FRW cosmology at large scales underwent a period of inflation at small scale.

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Bruno Carneiro da Cunha, Emil J. Martinec. 2003-04-14. Closed String Tachyon Condensation and Worldsheet Inflation. https://doi.org/10.1103/physrevd.68.063502

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