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arXiv · hep-th/9905043

One-Loop Tachyon Amplitude in Unoriented Open-Closed String Field Theory

Tsuguhiko Asakawa·Taichiro Kugo·Tomohiko Takahashi
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Abstract

We calculate one-loop 2-point tachyon amplitudes in unoriented open-closed string field theory, and determine all the coupling constants of the interaction vertices in the theory. It is shown that the planar, nonplanar and nonorientable amplitudes are all reproduced correctly, and nontrivial consistencies between the determined coupling constants are observed. The necessity for the gauge group to be SO(2^{13}=8192) is also reconfirmed.

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Tsuguhiko Asakawa, Taichiro Kugo, Tomohiko Takahashi. 1999-05-20. One-Loop Tachyon Amplitude in Unoriented Open-Closed String Field Theory. https://doi.org/10.1143/ptp.102.427

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