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Semi-localized instability of the Kaluza-Klein linear dilaton vacuum

Oren Bergman·Shinji Hirano
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Abstract

The Kaluza-Klein linear dilaton background of the bosonic string and the Scherk-Schwarz linear dilaton background of the superstring are shown to be unstable to the decay of half of spacetime. The decay proceeds via a condensation of a semi-localized tachyon when the circle is smaller than a critical size, and via a semiclassical instanton process when the circle is larger than the critical size. At criticality the two pictures are related by a duality of the corresponding two-dimensional conformal field theories. This provides a concrete realization of the connection between tachyonic and semiclassical instabilities in closed string theory, and lends strong support to the idea that non-localized closed string tachyon condensation leads to the annihilation of spacetime.

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Oren Bergman, Shinji Hirano. 2005-10-27. Semi-localized instability of the Kaluza-Klein linear dilaton vacuum. https://doi.org/10.1016/j.nuclphysb.2006.03.024

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