Browsing Theses by Subject "cosmology"
Now showing items 1-18 of 18
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Assessing the Accuracy of Cosmological Parameters Estimated from Velocity – Density Comparisons
(University of Waterloo, 2024-01-10)A promising method for measuring the cosmological parameter combination fσ₈ is to compare observed peculiar velocities with peculiar velocities predicted from a galaxy density field using linear perturbation theory, known ... -
Can Lensing Measure The Shape Of Dark Matter Halos?
(University of Waterloo, 2012-09-27)The aim of this project was to explore the shapes of dark matter halos using high resolution N-body simulations. One of the main aspects explored was how well the shape can be measured through weak lensing. To explore this, ... -
Cosmic Acceleration As Quantum Gravity Phenomenology
(University of Waterloo, 2010-09-22)The discovery of cosmic acceleration has prompted the need for a new understanding of cosmology. The presence of this acceleration is often described as the dark energy problem or the Lambda problem.The simplest explanation ... -
Cosmology with Cluster Structural Properties
(University of Waterloo, 2023-06-23)Galaxy clusters are massive objects composed of hundreds or thousands of galaxies, hot gas and an extended dark matter (DM) halo. They are the largest gravitationally bound structures in the Universe. As such, they result ... -
A Covariant Natural Ultraviolet Cutoff in Inflationary Cosmology
(University of Waterloo, 2013-08-28)In the field of quantum gravity, it is widely expected that some form of a minimum length scale, or ultraviolet cutoff, exists in nature. Recently, a new natural ultraviolet cutoff that is fully covariant was proposed. In ... -
The Dynamics of Inhomogeneous Cosmologies
(University of Waterloo, 2004)In this thesis we investigate cosmological models more general than the isotropic and homogeneous Friedmann-Lemaître models. We focus on cosmologies with one spatial degree of freedom, whose matter content ... -
Exact and Perturbed Friedmann-Lemaitre Cosmologies
(University of Waterloo, 2007-08-07)In this thesis we first apply the 1+3 covariant description of general relativity to analyze n-fluid Friedmann-Lemaitre (FL) cosmologies; that is, homogeneous and isotropic cosmologies whose matter-energy content consists ... -
An Exploration of Clustering Statistics and Tidal Alignments in the Context of Group Catalogues
(University of Waterloo, 2021-10-04)The use of three-dimensional galaxy surveys and large cosmological simulations of the galaxy distribution has advanced our understanding of large-scale structure over the last few decades. At the forefront of this are ... -
Late-universe signals in the microwave sky: extragalactic dust, electrons, and other baryonic effects
(University of Waterloo, 2021-06-07)This thesis collects much of the work I have done over the last four years as a PhD student. It has two focuses. Part 1 discusses gravitational radiation emitted from two maximally charged black holes in Einstein--Maxwell--dilaton ... -
Optimizing Small-scale Redshift Space Distortion Measurements in eBOSS for Cosmological Inference
(University of Waterloo, 2023-09-21)Modern cosmological datasets have grown substantially in size and the precision of their measurements. While the improvement has had a beneficial impact on our understanding of the cosmological model, it requires equal ... -
Path Integrals in the Sky: Classical and Quantum Problems with Minimal Assumptions
(University of Waterloo, 2019-10-24)Cosmology has, after the formulation of general relativity, been transformed from a branch of philosophy into an active field in physics. Notwithstanding the significant improvements in our understanding of our Universe, ... -
Precision Cosmology Using Voids
(University of Waterloo, 2023-08-04)In the late 1990s, the discovery that the expansion rate of the Universe was accelerating was a decisive moment for cosmology. The last 25 years have seen the consolidation of this component, called dark energy, which ... -
Probing the large-scale clustering of fast radio bursts with CHIME/FRB
(University of Waterloo, 2021-08-23)Explaining the nature of extragalactic fast radio bursts (FRBs) has puzzled astrophysicists since 2007. In this thesis, we introduce the CHIME/FRB instrument, an FRB search engine that could solve this puzzle through FRB ... -
Spectrum of Cuscuton Bounce and Cosmological Parameter Inference Using Dark Sirens
(University of Waterloo, 2021-08-25)Over the last couple of decades, cosmology has become an exciting area to study. Technological developments in both the computational and observational fronts have propelled cosmology into the limelight of modern physics. ... -
A Subclass of Exceptional Parallel Self-similar G2 Cosmologies
(University of Waterloo, 2019-05-13)We perform a qualitative and asymptotic analysis of a particular class of cosmological models, namely the exceptional G2 perfect fluid and vacuum models that are additionally self-similar with the fluid flow lying tangential ... -
Thinking outside the box; fast error estimation for next generation galaxy surveys
(University of Waterloo, 2024-01-29)Since the discovery of the accelerated expansion of the universe in the late 90s, the flat $\Lambda$CDM model has reigned as the best explanation for the cosmological phenomena we have observed. In spite of over two decades ... -
Topics in early and late Universe cosmology
(University of Waterloo, 2020-08-11)In this thesis, we explore different problems in various areas of cosmology. The inflationary paradigm has been very successful in explaining cosmological observations. However, some problems still linger on. In the ... -
Universe Beyond Inflation and ΛCDM
(University of Waterloo, 2021-09-09)The current paradigm of universe, $\Lambda CDM$ model with an early phase of inflation, has been quite successful in describing our universe in a simple manner, yet matching well with the observational evidence. This model ...