Year: 2026
Type: article
Abstract: We study a timelike thin-shell gravastar whose exterior is the Schwarzschild-like vacuum of bumblebee gravity, with radial Lorentz-violating (LV) vacuum expectation value and ℓ = 𝜉 𝑏 2 . A constant-radial-factor de Sitter metric is used only as a no-go diagnostic: its Einstein tensor requires a singular anisotropic source, its Kretschmann scalar diverges at the center, and it violates the frozen bumblebee field equation for ℓ ≠ 0. A regular core must therefore screen, reorient, or expel the radial condensate. We match an ordinary de Sitter core to the bumblebee exterior across a thin but finite timelike wall and derive the total effective surface density and pressure, the shell mass relation, compactness condition, and radial stability potential. Positive ℓ reduces the exterior contribution to the surface stress by ( 1 + ℓ ) − 1 / 2 and enlarges radial proper and optical lengths by √ 1 + ℓ . The photon-sphere radius and critical impact parameter remain 3 M and 3 √ 3 𝑀 at fixed lapse mass, whereas the background-subtracted bending and radial travel time retain an ℓ dependence. The asymptotic geometry is conical, so the lapse parameter M is distinguished from the background-subtracted mass 𝑀 / √ 1 + ℓ . The construction is restricted to the timelike Visser-Wiltshire domain 2 M < R < L and does not apply to the distinct null common-horizon limit 𝑅 = 𝐿 = 2 𝑀 . An illustrative two-order-parameter screening potential is supplied, but neither a self-consistent microscopic wall nor a detectable value of ℓ is claimed.
Source: Physics Letters B
Authors: F.M. Belchior, A.R.P. Moreira, M. Sharif
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W7221180692