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arXiv · 2405.17056

Massive twistor worldline in electromagnetic fields

Joon-Hwi Kim·Jung-Wook Kim·Sangmin Lee
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Abstract

We study the (ambi-)twistor model for spinning particles interacting via electromagnetic field, as a toy model for studying classical dynamics of gravitating bodies including effects of both spins to all orders. We compute the momentum kick and spin kick up to one-loop order and show precisely how they are encoded in the classical eikonal. The all-orders-in-spin effects are encoded as a dynamical implementation of the Newman-Janis shift, and we find that the expansion in both spins can be resummed to simple expressions in special kinematic configurations, at least up to one-loop order. We confirm that the classical eikonal can be understood as the generator of canonical transformations that map the in-states of a scattering process to the out-states. We also remark that cut contributions for converting worldline propagators from time-symmetric to retarded amount to the iterated action of the leading eikonal at one-loop order.

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Joon-Hwi Kim, Jung-Wook Kim, Sangmin Lee. 2024-05-27. Massive twistor worldline in electromagnetic fields. https://doi.org/10.1007/jhep08(2024)080

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