On KLT and SYM-supergravity relations from 5-point 1-loop amplitudes

TL;DR

This paper introduces a new non-singular KLT relation for 5-point amplitudes with enhanced symmetry, derived from one-loop amplitudes and IR divergences, and explores its extension to higher points and relations to supergravity.

Contribution

It presents a novel non-singular KLT relation for 5-point amplitudes with manifest symmetry, derived from one-loop amplitude analysis, and proposes a connection between SYM and supergravity amplitudes.

Findings

Derived a new non-singular 5-point KLT relation with $2(n-2)!$ symmetry.

Showed that subleading-color ${ m N}=4$ SYM 5-point amplitude has a $1/\epsilon$ IR divergence.

Proposed a relation between subleading-color ${\rm N}=4$ SYM and ${\rm N}=8$ supergravity 1-loop 5-point amplitudes.

Abstract

We derive a new non-singular tree-level KLT relation for the $n=5$-point amplitudes, with manifest $2(n-2)!$ symmetry, using information from one-loop amplitudes and IR divergences, and speculate how one might extend it to higher n-point functions. We show that the subleading-color ${\cal N}=4$ SYM 5-point amplitude has leading IR divergence of $1/\epsilon$, which is essential for the applications of this paper. We also propose a relation between the subleading-color ${\cal N}=4$ SYM and ${\cal N}=8$ supergravity 1-loop 5-point amplitudes, valid for the IR divergences and possibly for the whole amplitudes, using techniques similar to those used in our derivation of the new KLT relation.