Anisotropic Cosmology with Inhomogeneous $SU(2) $ and $SL(2,\mathbb{R})$ Nonlinear $σ$-Models
Year: 2026
Type: preprint
Abstract: We investigate the cosmological dynamics of the nonlinear $σ$-model in a locally rotational symmetric Bianchi V background geometry. We employ the $SU(2)$ and the $SL(2,\mathbb{R})$ internal symmetries, for which the kinetic metric of the multi-scalar fields is a space of constant curvature. We assume an inhomogeneous ansatz for the scalar fields, such that the $σ$-model, which allows the existence of nontrivial solutions in the Bianchi V geometry. For an exponential potential, we perform a detailed analysis of the phase space, we determine the stationary points, and we study their stability properties. The scalar field inhomogeneities prevent both the slow-roll and hyperbolic inflationary epochs. The existence of a cosmological constant is required to describe cosmic acceleration.
Source: arXiv (Cornell University)
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funder: Universidad Católica del Norte
Awards: G1701937586, G4586750831
OpenAlex ID: W7221024294