Use this URL to cite or link to this record in EThOS:
Title: Computational ultrarelativistic hydrodynamics
Author: Hawke, I.
Awarding Body: University of Cambridge
Current Institution: University of Cambridge
Date of Award: 2002
Availability of Full Text:
Full text unavailable from EThOS.
Please contact the current institution’s library for further details.
This thesis studies critical collapse in the early universe as modelled by a Friedman-Robertson-Walker (FRW) spacetime. This differs from most previous studies of critical collapse as the spacetime is not asymptotically flat or approximately stationary. This study allows us to look at the formation of black holes in the early universe. In order to perform this study we consider in depth the numerical methods necessary to study the collapse of an ultrarelativistic fluid. The general solution of the Riemann problem with the ultrarelativistic equation of state is derived, along with previous results. The efficiency and accuracy of different exact and approximate Riemann solvers is compared. The Riemann solvers are then used to implement and test a number of High Resolution Shock Capturing methods. A variety of high order methods are compared using a wide variety of test. The stability, accuracy and efficiency of the methods are the focus of this part of the thesis. These methods are combined with different gridding strategies. The Adaptive Mesh Refinement algorithm is described, together with simpler methods such as an uneven grid. The Adaptive Mesh algorithm is found to have some unexpected problems when the system of equations is not hyperbolic. Finally we look at the behaviour of the collapse of a density perturbation in a FRW spacetime. It is shown that it does not conform to the standard critical collapse scenario. Various explanations for this are discussed, together with the implications for primordial black hole formation.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available