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arXiv · 2412.02034

One-Loop Observables to Higher Order in Spin

Juan Pablo Gatica
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Abstract

We study observables in the scattering of classical, spinning objects using the KMOC formalism. In particular, we derive formulas to higher order in spin and one loop $\mathcal{O}(G^2)$ for the spin kick and momentum impulse. Our derivation method is agnostic to the choice of theory or special conditions, such as the spin supplementary condition (SSC); we only rely on the generic structure of long-range scattering amplitudes of non-transverse, massive spinning fields in the classical limit. We check these formulas for the case of gravity and agree with previous results from the eikonal formalism after imposing a SSC.

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Juan Pablo Gatica. 2024-12-02. One-Loop Observables to Higher Order in Spin. https://arxiv.org/abs/2412.02034

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