Bulk viscous fluid in symmetric teleparallel cosmology: theory versus experiment

Abstract

The standard formulation of General Relativity Theory, in the absence of a cosmological constant, is unable to explain the responsible mechanism for the observed late-time cosmic acceleration. On the other hand, by inserting the cosmological constant in Einstein's field equations it is possible to describe the cosmic acceleration, but the cosmological constant suffers from an unprecedented fine-tunning problem. This motivates one to modify Einstein's space-time geometry of General Relativity. The $f(Q)$ modified theory of gravity is an alternative theory to General Relativity, where the non-metricity scalar $Q$ is the responsible candidate for gravitational interactions. In the present work we consider a Friedmann-Lemâitre-Robertson-Walker cosmological model dominated by bulk viscous cosmic fluid in $f(Q)$ gravity with the functional form $f(Q)=\alpha Q^n$, where $\alpha$ and $n$ are free parameters of the model. We constrain our model with the recent Pantheon supernovae data set of 1048 data points, Hubble data set of 31 data points and baryon acoustic oscillations data set consisting of six points. For higher values of redshift, it is clear that the $f(Q)$ cosmology better fits data than standard cosmology. We present the evolution of our deceleration parameter with redshift and it properly predicts a transition from decelerated to accelerated phases of the universe expansion. Also, we present the evolution of density, bulk viscous pressure and the effective equation of state parameter with redshift. Those show that bulk viscosity in a cosmic fluid is a valid candidate to acquire the negative pressure to drive the cosmic expansion efficiently.We also examine the behavior of different energy conditions to test the viability of our cosmological $f(Q)$ model. Furthermore, the statefinder diagnostics are also investigated in order to distinguish among different dark energy models.

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References in corpus (33)

• Dark energy in modified Gauss-Bonnet gravity: late-time acceleration and the hierarchy problem
• Conditions for the cosmological viability of f(R) dark energy models
• The teleparallel equivalent of general relativity
• Large Scale Structure as a Probe of Gravitational Slip
• The Cosmology of Modified Gauss-Bonnet Gravity
• Correcting Type Ia Supernova Distances for Selection Biases and Contamination in Photometrically Identified Samples
• Dark matter as a geometric effect in f(R) gravity
• Energy Conditions in $f(Q)$ gravity
• Eppur è piatto? The cosmic chronometer take on spatial curvature and cosmic concordance
• Testing $F(Q)$ gravity with redshift space distortions
• Signatures of $f(Q)$-gravity in cosmology
• Accelerated Expansion of the Universe in Non-minimally Coupled Gravity
• Cosmography in $f(Q)$ gravity
• Bulk Viscous Cosmology
• Model-independent reconstruction of $f(Q)$ non-metric gravity
• Friedmann model with viscous cosmology in modified $f(R,T)$ gravity theory
• Observational constraints on cosmological solutions of $f(Q)$ theories
• Can $f(Q)$ gravity challenge $\Lambda$CDM?
• A new interacting two fluid model and its consequences
• Bulk Viscosity, Decaying Dark Matter, and the Cosmic Acceleration
• Friedmann cosmology with bulk viscosity: a concrete model for dark energy
• A designer approach to $f(Q)$ gravity and cosmological implications
• f(R) Gravity: From the Pioneer Anomaly to the Cosmic Acceleration
• Bulk viscosity of superfluid neutron stars
• Data-driven Reconstruction of the Late-time Cosmic Acceleration with f(T) Gravity
• FRW in quadratic form of $f(T)$ gravitational theories
• Testing the equation of state for viscous dark energy
• Forecasting F(Q) cosmology with $\Lambda$CDM background using standard sirens
• Bulk viscosity of superfluid hyperon stars
• Viscosity in modified gravity
• Linear connections with propagating spin-3 field in gravity
• Black Holes in the Turbulent Phase of Viscous Rip Cosmology
• Quantum Cosmology in $f(Q)$ theory

Cited by in corpus (2)

• On the impact of $f(Q)$ gravity on the Large Scale Structure
• Cosmological constraints in symmetric teleparallel gravity with bulk viscosity