Modified cosmology from extended entropy with varying exponent
arXiv:1903.03098 · doi:10.1140/epjc/s10052-019-6740-5
Abstract
We present a modified cosmological scenario that arises from the application of non-extensive thermodynamics with varying exponent. We extract the modified Friedmann equations, which contain new terms quantified by the non-extensive exponent, possessing standard CDM cosmology as a subcase. Concerning the universe evolution at late times we obtain an effective dark energy sector, and we show that we can acquire the usual thermal history, with the successive sequence of matter and dark-energy epochs, with the effective dark-energy equation-of-state parameter being in the quintessence or in the phantom regime. The interesting feature of the scenario is that the above behaviors can be obtained even if the explicit cosmological constant is set to zero, namely they arise purely from the extra terms. Additionally, we confront the model with Supernovae type Ia and Hubble parameter observational data, and we show that the agreement is very good. Concerning the early-time universe we obtain inflationary de Sitter solutions, which are driven by an effective cosmological constant that includes the new terms of non-extensive thermodynamics. This effective screening can provide a description of both inflation and late-time acceleration with the same parameter choices, which is a significant advantage.
10 pages, 2 figures, to appear in Eur.Phys.J. C
References in corpus (18)
- Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
- Dark torsion as the cosmic speed-up
- Covariant Galileon
- Modified f(R) gravity consistent with realistic cosmology: from matter dominated epoch to dark energy universe
- Thermodynamic Behavior of Friedmann Equation at Apparent Horizon of FRW Universe
- Unified First Law and Thermodynamics of Apparent Horizon in FRW Universe
- Cosmological perturbations in f(T) gravity
- Friedmann Equations of FRW Universe in Scalar-tensor Gravity, f(R) Gravity and First Law of Thermodynamics
- Thermodynamic route to Field equations in Lanczos-Lovelock Gravity
- Hawking Radiation of Apparent Horizon in a FRW Universe
- Teleparallel equivalent of Gauss-Bonnet gravity and its modifications
- Thermodynamical Properties of Apparent Horizon in Warped DGP Braneworld
- Cosmological applications of gravity
- New observational constraints on gravity from cosmic chronometers
- Dynamical analysis of generalized Galileon cosmology
- The generalized second law of thermodynamics in Horava-Lifshitz cosmology
- Fourth order Weyl gravity
- Thermodynamical First Laws of Black Holes in Quadratically-Extended Gravities