Year: 2026
Type: article
Abstract: A bstract 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, spin representation, 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 up to quadratic order in spin and agree with previous results from the eikonal formalism after imposing a SSC. This is the first derivation of its kind using KMOC and field theory to derive formulas directly relating amplitudes to observables to general order in spin without relying on a truncation in the spin expansion.
Source: Journal of High Energy Physics
Author: Juan Pablo Gatica
Institution: University of California, Los Angeles
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
Funder: U.S. Department of Energy
OpenAlex ID: W7125980949