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arXiv · 2412.14126

Gravitational lensing in a plasma from worldlines

Francesco Comberiati·Leonardo de la Cruz
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Abstract

We study the deflection of light rays in a cold, non-magnetized plasma using the worldline framework. Starting from Synge's Hamiltonian formalism, we construct a position-space action and use it perturbatively to calculate light bending angles. In the homogeneous case, the action reduces to that of a massive particle, allowing us to extract the bending angle of light in the presence of the medium using a well-known analogy. For the inhomogeneous case, we consider a power law model and construct Feynman rules in time to compute the purely plasma-induced corrections to the bending angle at Next-to-Leading-Order (NLO).

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Francesco Comberiati, Leonardo de la Cruz. 2024-12-18. Gravitational lensing in a plasma from worldlines. https://arxiv.org/abs/2412.14126

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