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arXiv · 2211.05795

Bounds on photon scattering

Kelian Häring·Aditya Hebbar·Denis Karateev·Marco Meineri·João Penedones
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Abstract

We study 2-to-2 scattering amplitudes of massless spin one particles in $d=4$ space-time dimensions, like real world photons. We define a set of non-perturbative observables (Wilson coefficients) which describe these amplitudes at low energies. We use full non-linear unitarity to construct various novel numerical bounds on these observables. For completeness, we also rederive some bounds using positivity only. We discover and explain why some of these Wilson coefficients cannot be bounded.

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Kelian Häring, Aditya Hebbar, Denis Karateev, Marco Meineri, João Penedones. 2022-11-10. Bounds on photon scattering. https://doi.org/10.1007/jhep10(2024)103

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