Reduction of Open String Amplitudes by Mostly BRST Exact Operators
Abstract
We study two and three-point tree-level amplitudes of open strings. These amplitudes are reduced from higher-point correlation functions by using mostly BRST exact operators for gauge fixing. For simplicity, we focus on an open string tachyon. The two-point amplitude of open string tachyons is reduced from a three-point function of two tachyon vertex operators and one mostly BRST exact operator. Similarly the three-point amplitude is from a four-point function of three tachyon vertex operators and one mostly BRST exact operator. One can also obtain the two-point amplitude from the four-point function of two tachyon vertex operators and two mostly BRST exact operators. In these derivation from four-point functions, moduli integrals are significant. We discuss the overall signs of amplitudes which are indefinite in this formalism.
Cite
@article{arxiv.2108.05628,
title = {Reduction of Open String Amplitudes by Mostly BRST Exact Operators},
author = {Shigenori Seki and Tomohiko Takahashi},
journal= {arXiv preprint arXiv:2108.05628},
year = {2021}
}
Comments
1+12 pages, 1 figure; v2: short explanation added in p. 7 and typos corrected