Cosmological and astrophysical observables from field theory in curved backgrounds

Resource type
Thesis type
(Thesis) Ph.D.
Date created
2019-05-03
Authors/Contributors
Author: Galvez, Jose
Abstract
The framework of effective field theory has provided valuable insights needed to understand the evolution of physical systems at different energy scales. In particular, when comparing the near-equilibrium phenomena at astrophysical scales with effects at cosmological distances. The objective of this thesis is to introduce useful tools for the evaluation of (a) the observational consistency of an effective field theory of gravity, and (b) the potential modifications of theories, equipped with diffeomorphism invariance. We calculate the evolution of gravitational observables relevant in early universe field configurations, and also in effective theories modified by contributions from higher curvature terms or semiclassical effects testable at astrophysical scales. To do so, we develop efficient numerical routines to resolve the dynamic two-point correlation functions of primordial fluctuations in inflationary and bouncing cosmologies, the accretion of scalar fields and spacetime curvature in modified gravity, and the evolution of scattering processes involving scalar and gravitational radiation. Additionally, we investigate the viability of defining gauge-invariant quantities in theories of gravity, where the canonical coordinates are deformed to incorporate extra degrees of freedom.
Identifier
etd20306
Copyright statement
Copyright is held by the author.
Permissions
This thesis may be printed or downloaded for non-commercial research and scholarly purposes.
Scholarly level
Supervisor or Senior Supervisor
Thesis advisor: Frolov, Andrei
Member of collection
Model
English