Born-Infeld black holes in bumblebee gravity

Abstract

We construct exact static and spherically symmetric charged solutions in bumblebee gravity minimally coupled to Born--Infeld electrodynamics, taking into account a spacelike vector norm and a vanishing cosmological constant. An independently varied Lagrange multiplier enforces the norm constraint and acquires a radial profile determined by the transverse electromagnetic pressure. The solutions include purely radial configurations and configurations with constant or varying temporal amplitudes. At $ξ=κ/2$, the varying temporal amplitude introduces an independent bumblebee field strength while preserving the metric of the constant temporal configuration. Moreover, the electric field remains bounded, and the temporal configurations admit smooth extensions across a simple future horizon under explicit regularity conditions. We derive the photon sphere and shadow radii for both metric and nonlinear electromagnetic propagation. The leading nonlinear corrections enlarge the shadow at fixed geometric charge, whereas the temporal amplitude enters through the charged lapse. Comparisons with observations of Sgr~A$^*$ and M87$^*$ provide conditional bounds on the charge and nonlinear scale. In addition, the adopted planetary perihelion allowances yield an illustrative sensitivity of $|ξ|(b^2+u_0^2)\lesssim2.6\times10^{-12}$ for a neutral solar exterior.