Examen de grado de magíster: Yanina López Bonilla defenderá su tesis “Relativistic Simulations of Domain Wall Collapse” este viernes 14 de agosto a las 09:30 AM en la Sala 208 de la Facultad de Ciencias PUCV.
La comisión será integrada por el académico Alessio Notari (Universitá di Roma Sapienza) junto a Jorge Noreña, Radouane Gannouji y Nelson Videla del IFIS PUCV.
Te dejamos el resumen de la tesis:
This thesis investigates the non-linear dynamics and evolution of a fundamental scalar field configuration. As a preliminary step, we employ an asymptotically Minkowski background to simulate the gravitational collapse of domain wall networks in the early universe. Motivated by recent stochastic nanohertz gravitational wave signals detected by Pulsar Timing Arrays, we explore how energetic cosmological phase transitions could produce topological defects that collapse into primordial black holes. A precise understanding of this defect evolution provides a crucial window into remote cosmic epochs. The foundational mechanism for the formation and subsequent collapse of these networks is modeled via a first-order phase transition featuring a “kink” profile. Previous studies on this matter often use codes that do not fully resolve the spacetime metric, and thus cannot properly model the formation of black holes. We aim to address this limitation by utilizing the full machinery of general relativity through the numerical relativity simulation codes GRTresna and GRChombo. We simulate the collapsing case and compare our results with a stable, non-collapsing setup. Additionally, a bias term is introduced into the potential to actively drive the collapse. While the present study focuses on spherical geometries, our 3-dimensional codes are capable of evolving arbitrary fields. Future research will leverage this capability, alongside the implementation of an apparent horizon finder and the inclusion of a realistic cosmological background.
