GTIIT-STU Optics Seminar
Title: Black hole scalarization with spontaneous symmetry breaking
Speaker: Dr. Sebastián García-Saenz
Southern University of Science and Technology (SUSTech)
Abstract
Spontaneous scalarization of black holes may be understood in the language of symmetry breaking, with the scalar field condensate serving as order parameter. This motivates the study of theories with more interesting symmetry breaking patterns, i.e. beyond the simplest real scalar case. I will present our results on the study of black hole scalarization in the context of the Einstein-Maxwell-scalar model with a complex scalar field. Through fully non-linear numerical calculations, we find that the breaking of the U(1) symmetry gives rise to a lifting of the degeneracy in the process of formation, accretion and radiation of the scalar cloud. Adding an electric charge to the scalar further leads to an interesting interplay between the scalarization and superradiance effects. In particular, we find that the combination of the two mechanisms, which we refer to as “tachyonic superradiance”, results in a very efficient extraction of energy from the black hole, exploiting both the tachyonic growth and superradiant emission.
Biography
Sebastián García-Saenz is a theoretical cosmologist working at the interface of early-universe physics, gravitation, and high-energy theory. His research spans a broad range of topics, including cosmic inflation, dark energy, particle astrophysics, and modified gravity. He is particularly interested in developing new theoretical frameworks to address the nature of dark energy and to explore alternative paradigms of inflation beyond standard models.
He received his Ph.D. in Physics from Columbia University in 2016. He subsequently held postdoctoral and research positions at the Institut d’Astrophysique de Paris and Imperial College London. Since 2021, he has been an Assistant Professor at the Southern University of Science and Technology (SUSTech).
His work has made notable contributions to the study of modified gravity theories, non-Gaussianity in multifield inflation, and the dynamics of higher-spin and Proca fields.