Study of the Quasi-isotropic Solution near the Cosmological Singularity in Presence of Bulk-Viscosity
| dc.creator | Carlevaro, Nakia | |
| dc.creator | Montani, Giovanni | |
| dc.date | 2007-11-13 | |
| dc.date | 2009-03-09 | |
| dc.date.accessioned | 2026-07-07T12:54:58Z | |
| dc.date.available | 2026-07-07T12:54:58Z | |
| dc.description | We analyze the dynamical behavior of a quasi-isotropic Universe in the presence of a cosmological fluid endowed with bulk viscosity. We express the viscosity coefficient as a power-law of the fluid energy density: $ζ=ζ_0ε^{s}$. Then we fix $s=1/2$ as the only case in which viscosity plays a significant role in the singularity physics but does not dominate the Universe dynamics (as requested by its microscopic perturbative origin). The parameter $ζ_0$ is left free to define the intensity of the viscous effects. Following the spirit of the work by E.M. Lifshitz and I.M. Khalatnikov on the quasi-isotropic solution, we analyze both Einstein and hydrodynamic equations up to first and second order in time. As a result, we get a power-law solution existing only in correspondence to a restricted domain of $ζ_0$. | |
| dc.description | 15 pages, no figure | |
| dc.identifier | https://arxiv.org/abs/0711.1952 | |
| dc.identifier | http://arxiv.org/abs/0711.1952 | |
| dc.identifier | Int. J. Mod. Phys. D 17, 881-896 (2008) | |
| dc.identifier | doi:10.1142/S0218271808012553 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/224122 | |
| dc.subject | General Relativity and Quantum Cosmology | |
| dc.subject | Astrophysics | |
| dc.title | Study of the Quasi-isotropic Solution near the Cosmological Singularity in Presence of Bulk-Viscosity | |
| dc.type | text |