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arXiv · 2602.10889

Wave Propagation and Effective Refraction in Lorentz-Violating Wormhole Geometries

Semra Gurtas Dogan·Omar Mustafa·Abdulkerim Karabulut·Abdullah Guvendi
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Abstract

We study the propagation of massless scalar waves in static, spherically symmetric Lorentz-violating wormhole spacetimes within a geometric-optical framework. Starting from a general metric characterized by an arbitrary lapse function and areal radius, we derive curvature invariants, establish regularity conditions at the wormhole throat, and reduce the Klein-Gordon equation to a Helmholtz-type radial wave equation. This formulation naturally leads to a position- and frequency-dependent effective refractive index determined by the underlying spacetime geometry and Lorentz-violating structure, resulting in effective frequency-dependent wave-optical behavior. We show that divergences of the refractive index coincide with Killing horizons, while curvature-induced turning points control reflection, transmission, and confinement of scalar waves. By analyzing constant, linear, and quadratic lapse profiles, we identify horizonless transmission regimes, asymmetric wave propagation, and multi-horizon trapping structures. Our results reveal that Lorentz violation can significantly modify wave-optical properties of curved spacetime, generating graded-index analogues and geometric confinement of modes without curvature singularities. This unified optical perspective provides a robust framework for investigating wave scattering, resonances, and potential observational signatures in Lorentz-violating gravitational backgrounds.

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Semra Gurtas Dogan, Omar Mustafa, Abdulkerim Karabulut, Abdullah Guvendi. 2026-02-11. Wave Propagation and Effective Refraction in Lorentz-Violating Wormhole Geometries. https://arxiv.org/abs/2602.10889

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