Thin-Shell Wormholes in Born--Infeld-Type Magnetic Spacetimes

Abstract

We investigate the radial stability, thermodynamic balance, and bilateral disk images of symmetric thin-shell wormholes built from Born--Infeld-type magnetic exteriors. The exact lapse and junction conditions define a fixed-mass family in which magnetic self-energy ties the nonlinear scale to the charge. The shell has negative energy density, although an inner sampled region satisfies the tangential null and intrinsic strong energy conditions. Linear radial perturbations yield unstable calibrated barotropic samples and stable sectors for the generalized and modified cosmic Chaplygin laws on selected real branches. Analytic horizon and large-radius limits explain the stability transitions and show how the modified linear pressure term can replace outer stability with finite radial intervals. Minimally coupled Maxwell rays traverse transparent junctions between exteriors with a common arctangent emission profile, viewed by a static observer. The wormhole-black-hole intensity difference separates transmitted disk light from emission removed by throat excision. Compared with static emitters, circular and plunging motion reduce the face-on intensities in the studied cases; inclined motion generates strong azimuthal contrast. Increasing the subcritical charge contracts the critical circle and permits more disk crossings near it in the optical samples. Under a reversible first law, flux cancellation gives isentropic motion at positive temperature, with entropy dependence left to a constitutive completion. These results distinguish geometric, material, and kinematic effects on shell support and disk illumination.