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arXiv · 2106.12600

Generalizations of the Double-Copy: the KLT Bootstrap

Huan-Hang Chi·Henriette Elvang·Aidan Herderschee·Callum R. T. Jones·Shruti Paranjape
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Abstract

We formulate a new program to generalize the double-copy of tree amplitudes. The approach exploits the link between the identity element of the KLT algebra and the KLT kernel, and we demonstrate how this leads to a set of KLT bootstrap equations that the double-copy kernel has to satisfy (in addition to locality constraints). We solve the KLT bootstrap equations perturbatively to find the most general higher-derivative corrections to the 4- and 5-point field theory KLT kernel. The new kernel generalizes the string KLT kernel and its associated monodromy relations. It admits new color-structures in the effective theories it double-copies. It provides distinct generalized KK and BCJ relations for the left and right single-color theories and is in that sense a heterotic-type double-copy. We illustrate the generalized double-copy in detail for 4d Yang-Mills theory with higher-derivative corrections that produce dilaton-axion-gravity with local operators up order $\nabla^{10} R^4$. Finally, we initiate a search for new double-copy kernels.

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Huan-Hang Chi, Henriette Elvang, Aidan Herderschee, Callum R. T. Jones, Shruti Paranjape. 2021-06-23. Generalizations of the Double-Copy: the KLT Bootstrap. https://doi.org/10.1007/jhep03(2022)077

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