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arXiv · 1812.03369

String amplitudes from field-theory amplitudes and vice versa

Song He·Fei Teng·Yong Zhang
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Abstract

We present an integration-by-parts reduction of any massless tree-level string correlator to an equivalence class of logarithmic functions, which can be used to define a field-theory amplitude via a Cachazo-He-Yuan (CHY) formula. The string amplitude is then shown to be the double copy of the field-theory one and a special disk/sphere integral. The construction is generic as it applies to any correlator that is a rational function of correct SL(2) weight. By applying the reduction to open bosonic/heterotic strings, we get a closed-form CHY integrand for the $(DF)^2+\text{YM}+\phi^3$ theory.

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Song He, Fei Teng, Yong Zhang. 2018-12-08. String amplitudes from field-theory amplitudes and vice versa. https://doi.org/10.1103/physrevlett.122.211603

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