On the Asymptotic Behavior of Magnetic Bianchi Class A Spacetimes
Year: 2026
Type: dissertation
Abstract: One suggested explanation for the observed uniformity of the cosmic microwave background radiation is a chaotic evolution of the early universe. This requires anisotropic cosmological models, homogeneous examples of which are the Bianchi models. We study the asymptotic behavior of non-tilted Bianchi I and II models near the Big Bang singularity, in vacuum and in the presence of a magnetic field. Starting from a system of differential equations in expansion-normalized variables, we establish existence and uniqueness and prove convergence in both time directions using the monotonicity principle. We then put data on the singularity, characterizing the asymptotic behavior of solutions, and prove existence and uniqueness of solutions given this data. Finally, in the magnetic Bianchi I case, we interpret this data geometrically in terms of the expansion-normalized Weingarten map, the mean curvature, a modification of the spatial metric and the magnetic field.
Authors: Broström, Gustav, Palmgren, Alvin
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7167157061