An investigation on gravitational entropy of cosmological models
arXiv:1912.01414 · doi:10.1142/S0218271821500516
Abstract
In this paper, we investigate the entropy of the free gravitational field for a given epoch for some well-known isotropic and anisotropic cosmologies. We use the definition of gravitational entropy proposed by Clifton, Ellis, and Tavakol, where the 2-index square root of the 4-index Bel-Robinson tensor is taken to be the energy momentum tensor for the free gravity. We examine whether, in the vicinity of the initial singularity, the ratio of the energy density of free gravity to that of matter density goes to zero, validating Penrose's conjecture on Weyl curvature. Whenever this is true, the gravitational entropy increases monotonically with time, leading to structure formation. For the models considered by us, we identify the conditions for which the Weyl curvature hypothesis is valid, and the assumptions under which it is validated, or otherwise.
12 pages, final form, accepted for publication in IJMPD
References in corpus (14)
- A luminous quasar at a redshift of z = 7.085
- Evidence for anisotropy of cosmic acceleration
- Probing cosmic isotropy with a new X-ray galaxy cluster sample through the scaling relation
- Information Entropy in Cosmology
- The trouble with Hubble: Local versus global expansion rates in inhomogeneous cosmological simulations with numerical relativity
- The Weyl curvature conjecture and black hole entropy
- Power-law cosmology, SN Ia, and BAO
- Conformally flat FRW metrics
- Gravitational entropy and the cosmological no-hair conjecture
- Thermodynamics and Lemaitre-Tolman-Bondi void models
- Thermodynamics of Shearing Massless Scalar Field Spacetimes is Inconsistent With the Weyl Curvature Hypothesis
- Transferring Energy in General Relativity
- On the gravitational entropy of accelerating black holes
- Cosmological Structure Formation