Exact Wormholes and Ernst-like Potentials in Einstein–Maxwell–Scalar Field Gravity

par Leonel Bixano (Centro de Investigación y de Estudios Avanzados, Mexico)

jeudi 17 sept. 2026, 14:00 → 15:00 Europe/Paris

Salle 1180, bâtiment E2 (Salle des séminaires )

In this talk, I will present an Ernst-like formulation for stationary axisymmetric solutions in Einstein-Maxwell-Scalar Field gravity. The main idea is to encode the gravitational, electromagnetic, and scalar degrees of freedom into a set of potentials, extending the standard Ernst formalism beyond the vacuum and Einstein-Maxwell sectors. I will first explain how this framework reproduces several known exact solutions, including Schwarzschild, Reissner-Nordström, Gibbons-Maeda, Kerr, and Kerr-Newman, showing how the metric functions and electromagnetic fields can be reconstructed from the potential-space variables.

 

After introducing the formalism, I will apply it to the construction of exact wormhole solutions. In particular, I will discuss a stationary axisymmetric wormhole branch supported by scalar-electromagnetic fields in Einstein-Maxwell-Dilaton gravity. The solution will be described through the complete set of functions (f,\omega,k,A_t,A_\varphi,\phi), and I will analyze its main geometric features, including the throat structure, the existence of two asymptotic regions, and the role of the ring singularity in the global spacetime. The goal is to show that these wormholes are not isolated examples, but arise naturally within a broader Ernst-like potential-space approach.