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arXiv · 0806.1491

N-point functions in rolling tachyon background

Niko Jokela·Matti Jarvinen·Esko Keski-Vakkuri
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Abstract

We study n-point boundary correlation functions in Timelike Boundary Liouville theory, relevant for open string multiproduction by a decaying unstable D-brane. We give an exact result for the one-point function of the tachyon vertex operator and show that it is consistent with a previously proposed relation to a conserved charge in string theory. We also discuss when the one-point amplitude vanishes. Using a straightforward perturbative expansion, we find an explicit expression for a tachyon n-point amplitude for all n, however the result is still a toy model. The calculation uses a new asymptotic approximation for Toeplitz determinants, derived by relating the system to a Dyson gas at finite temperature.

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Niko Jokela, Matti Jarvinen, Esko Keski-Vakkuri. 2009-04-20. N-point functions in rolling tachyon background. https://doi.org/10.1103/physrevd.79.086013

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