Year: 2026
Type: article
Abstract: We investigate the shadow cast by a rotating traversable wormhole in the Teo class endowed with a general redshift function, with particular emphasis on the emergence of cuspy structures. The shadow boundary is the common envelope of two critical orbit families: unstable circular orbits outside the throat and orbits at the throat itself. The formation of cusps, marking the transition between smooth and cuspy shadow boundaries, only becomes possible when the redshift parameter $$\lambda $$ λ is allowed to vary. Moreover, we uncover a universal critical value $$\lambda _c=(\sqrt{5}-1)/4$$ λ c = ( 5 - 1 ) / 4 that signals the onset of the cusp. A phase diagram characterized by the spin and redshift parameters reveals four distinct morphologies: smooth, cuspy, ears touching, and throat drowning. The morphology of the wormhole shadow may provide observational diagnostics for the different compact objects in future high-resolution imaging observations.
Source: The European Physical Journal C
Authors: Peng Cheng, Ruo-Fan Xu, Peng Zhao
Institution: Tianjin University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
Awards: G4317857312, G72192826, G8056282666
OpenAlex ID: W7153275084