A Numerical Study of Relativistic Fluid Collapse

Abstract

We investigate the dynamics of self-gravitating, spherically-symmetric distributions of fluid through numerical means. In particular, systems involving neutron star models driven far from equilibrium in the strong-field regime of general relativity are studied. Hydrostatic solutions of Einstein's equations using a stiff, polytropic equation of state are used for the stellar models. Many of the scenarios we examine involve highly-relativistic flows that require improvements upon previously published numerical methods to simulate. Here our particular focus is on the physical behavior of the coupled fluid-gravitational system at the threshold of black hole formation--so-called black hole critical phenomena. To investigate such phenomena starting from conditions representing stable stars, we must drive the star far from its initial stable configuration. We use one of two different mechanisms to do this: setting the initial velocity profile of the star to be in-going, or collapsing a shell of massless scalar field onto the star. Both of these approaches give rise to a large range of dynamical scenarios that the star may follow. These scenarios have been extensively surveyed by using different initial star solutions, and by varying either the magnitude of the velocity profile or the amplitude of the scalar field pulse. In addition to illuminating the critical phenomena associated with the fluid collapse, the resulting phase diagram of possible outcomes provides an approximate picture of the stability of neutron stars to large, external perturbations that may occur in nature.

228 pages, 66 Postscript figures, Ph.D. Thesis, the University of Texa s at Austin, uses utdiss2.sty v5

References in corpus (8)

• The Dynamics of General Relativity
• Observation of critical phenomena and self-similarity in the gravitational collapse of radiation fluid
• Critical Behaviour in Gravitational Collapse of a Yang-Mills Field
• Kaon Condensation in Proto-Neutron Star Matter
• Critical phenomena in perfect fluids
• Scaling of curvature in sub-critical gravitational collapse
• General Relativistic Hydrodynamics with Special Relativistic Riemann Solvers
• Critical Collapse of Skyrmions

Cited by in corpus (6)

• A New Open-Source Code for Spherically-Symmetric Stellar Collapse to Neutron Stars and Black Holes
• Discontinuous Galerkin methods for general-relativistic hydrodynamics: formulation and application to spherically symmetric spacetimes
• A numerical exploration of first-order relativistic hydrodynamics
• Electromagnetic Emission from a Binary Black Hole Merger Remnant in Plasma: Field Alignment and Plasma Temperature
• Stability and Observability of Magnetic Primordial Black Hole-Neutron Star Collisions
• Refining a relativistic, hydrodynamic solver: Admitting ultra-relativistic flows