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arXiv · 2308.16142

Closed string tachyon condensation revisited

Jaroslav Scheinpflug·Martin Schnabl
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Abstract

We consider condensation of nearly marginal matter tachyons in closed string field theory and observe that upon restricting to a subspace of states not containing the ghost dilaton, the on-shell value of the action is proportional to the shift of the central charge of the matter CFT. This correspondence lets us find a novel conformal perturbation theory formula for the next-to-leading order shift of the central charge for a generic theory, which we test on Zamolodchikov's flow between consecutive minimal models. Upon reintroduction of the dilaton couplings, it is plausible to have a vanishing value of the on-shell action.

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Jaroslav Scheinpflug, Martin Schnabl. 2023-08-30. Closed string tachyon condensation revisited. https://arxiv.org/abs/2308.16142

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