2020/08/29 by Jamie I. McDonald, McDonald, Jamie I., Luís B. Ventura +1
Engineering · Physics and Astronomy · #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Phenomenology (hep-ph) #Optical Polarization and Ellipsometry #Stellar, planetary, and galactic studies #gr-qc #hep-ph
paper · pdf · doi:10.48550/arxiv.2008.12923
14 pages, 7 figures. Comments are welcome
arxiv created 2020/08/29 · openalex publication_date 2020/08/29 · arxiv updated 2020/09/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this work we examine refraction of light by computing full solutions to axion electrodynamics. We also allow for the possibility of an additional plasma component. We then specialise to wavelengths which are small compared to background scales to determine if refraction can be described by geometric optics. We also allow for the possibility of an additional plasma component. In the absence of plasma, for small incidence angles relative to the optical axis, axion electrodynamics and geometric optics are in good agreement, with refraction occurring at O(ga γγ2). However, for rays which lie far from the optical axis, the agreement with geometric optics breaks down and the dominant refraction requires a full wave-optical treatment, occurring at O(ga γγ). In the presence of sufficiently large plasma masses, the wave-like nature of light becomes suppressed and geometric optics is in good agreement with the full theory for all rays. Our results therefore suggest the necessity of a more comprehensive study of lensing and ray-tracing in axion backgrounds, including a full account of the novel O(ga γγ) wave-optical contribution to refraction.