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arXiv · 2505.01501

Universality of Colored Scalars from the Stringy KLT Kernel

Christoph Bartsch·Karol Kampf·Jiří Novotný·Jaroslav Trnka
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Abstract

A new perspective on the inverse string theory Kawai-Lewellen-Tye (KLT) kernel is provided which establishes the universality of scattering amplitudes in the bi-adjoint scalar (BAS) theory, pions in the Non-linear sigma model (NLSM), and mixed amplitudes (NLSM+$ϕ^3$) recently studied in the literature. We show that all these amplitudes can be viewed as equivalent, arising from a single function, the inverse string theory KLT kernel, evaluated at different kinematic points. In this way cubic colored scalars and pions become interchangeable through a procedure we call the $α'$-shift. The latter complements the $δ$-shift proposed by Arkani-Hamed et al., and demonstrates an inherent equivalence of scattering amplitudes in different quantum field theories by embedding them in a common stringy framework.

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Christoph Bartsch, Karol Kampf, Jiří Novotný, Jaroslav Trnka. 2025-05-02. Universality of Colored Scalars from the Stringy KLT Kernel. https://arxiv.org/abs/2505.01501

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