Cosmological constraints on polytropic gas model

Abstract

We study the polytropic gas scenario as the unification of dark matter and dark energy. We fit the model parameters by using the latest observational data including type Ia supernovae, baryon acoustic oscillation, cosmic microwave background, and Hubble parameter data. At 68.3% and 95.4% confidence levels, we find the best fit values of the model parameters as $\tilde{K}=0.742_{-0.024}^{+0.024}(1\sigma {)}_{-0.049}^{+0.048}(2\sigma )$ and $n=-1.05_{-0.08}^{+0.08}(1\sigma {)}_{-0.16}^{+0.15}(2\sigma )$. Using the best fit values of the model, we obtain the evolutionary behaviors of the equation of state parameters of the polytropic gas model and dark energy, the deceleration parameter of the universe as well as the dimensionless density parameters of dark matter and dark energy. We conclude that in this model, the universe starts from the matter dominated epoch and approaches a de Sitter phase at late times, as expected. Also the universe begins to accelerate at redshift $z_{\mathrm{t}}=0.74$. Furthermore in contrary to the $\Lambda$CDM model, the cosmic coincidence problem is solved naturally in the polytropic gas scenario.

13 pages, 7 figures, 2 tables

References in corpus (22)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• New Hubble Space Telescope Discoveries of Type Ia Supernovae at z > 1: Narrowing Constraints on the Early Behavior of Dark Energy
• Cosmological Constraints from the SDSS Luminous Red Galaxies
• Spectra and Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
• A test of the nature of cosmic acceleration using galaxy redshift distortions
• A New Model of Agegraphic Dark Energy
• A Holographic Dark Energy Model from Ricci Scalar Curvature
• Confirmation of general relativity on large scales from weak lensing and galaxy velocities
• Cosmography in f(T)-gravity
• Matter density perturbations and effective gravitational constant in modified gravity models of dark energy
• The 2dF-SDSS LRG and QSO Survey: QSO clustering and the L-z degeneracy
• Growth factor in f(T) gravity
• The 2dF-SDSS LRG and QSO Survey: The LRG 2-Point Correlation Function and Redshift-Space Distortions
• Cosmological Constraints on New Agegraphic Dark Energy
• Attractor Solutions in f(T) Cosmology
• Interacting entropy-corrected new agegraphic dark energy in Brans-Dicke cosmology
• Cosmic accelerated expansion and the entropy corrected holographic dark energy
• Cosmic coincidence problem and variable constants of physics
• Interacting modified Chaplygin gas in loop quantum cosmology
• Statefinder diagnostic and $w-w^{\prime }$ analysis for interacting polytropic gas dark energy model
• Reconstructing interacting new agegraphic polytropic gas model in non-flat FRW universe
• Polytropic gas scalar field models of dark energy

Cited by in corpus (11)

• Polytropic dark matter flows illuminate dark energy and accelerated expansion
• Dark Energy: The Shadowy Reflection of Dark Matter?
• A note on the relations between thermodynamics, energy definitions and Friedmann equations
• Thermodynamic behavior and stability of Polytropic gas
• Black holes immersed in polytropic scalar field gas
• On the Cosmological Models with Matter Creation
• Thermodynamic descriptions of Polytropic gas and its viscous type as the dark energy candidates
• Cosmological perturbations in the $\Lambda$CDM-like limit of a polytropic dark matter model
• Structure Formation in Dark Matter Particle Production Cosmology
• The $D$-dimensional charged AdS black holes solutions in polytropic dark energy from Barrow entropy
• Chaplygin and Polytropic gases Teleparallel Robertson-Walker $F(T)$ gravity solutions