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arXiv · 2109.08433

The Veneziano Amplitude via Mostly BRST Exact Operator

Isao Kishimoto·Tomoko Sasaki·Shigenori Seki·Tomohiko Takahashi
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Abstract

The Veneziano amplitude is derived from fixing one degree of freedom of $PSL(2,\mathbb{R})$ symmetry by the insertion of a mostly BRST exact operator. Evaluating the five-point function which consists of four open string tachyons and this gauge fixing operator, we find it equals the Veneziano amplitude up to a sign factor. The sign factor is interpreted as a signed intersection number.The result implies that the mostly BRST exact operator, which is originally used to provide two-point string amplitudes, correctly fixes the $PSL(2,\mathbb{R})$ gauge symmetry for general amplitudes. We conjecture an expression for general $n$-point tree amplitudes with an insertion of this gauge fixing operator.

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Isao Kishimoto, Tomoko Sasaki, Shigenori Seki, Tomohiko Takahashi. 2021-09-17. The Veneziano Amplitude via Mostly BRST Exact Operator. https://doi.org/10.1016/j.nuclphysb.2021.115647

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