Constraining the cosmological model of modified $f(Q)$ gravity: Phantom dark energy and observational insights

Abstract

Despite the significant accomplishments of general relativity, numerous unresolved issues persist in our understanding of the cosmos. One of the most perplexing challenges is the ongoing accelerated expansion of the Universe, which continues to elude a complete explanation. Consequently, scientists have proposed various alternative theories to GR in pursuit of a deeper understanding. In our analysis, we delve into the recently proposed modified $f(Q)$ gravity, where $Q$ represents the non-metricity scalar responsible for gravitational effects. Specifically, we investigate a cosmological model characterized by the functional form $f(Q)=Q+\alpha Q^n$, where $\alpha$ (with $\alpha \ne 0$) and $n$ serve as free parameters. Utilizing this functional form, we construct our Hubble rate, incorporating a specific equation of state to describe the cosmic fluid. Furthermore, we leverage a dataset consisting of 31 data points from Hubble measurements and an additional 1048 data points from the Pantheon dataset. These data serve as crucial constraints for our model parameters, and we employ the Markov Chain Monte Carlo (MCMC) method to explore the parameter space and derive meaningful results. With our parameter values constrained, our analysis yields several noteworthy findings. The deceleration parameter suggests a recent accelerated phase in the cosmic expansion. In addition, the EoS parameter paints a portrait of dark energy exhibiting phantom-like characteristics. Furthermore, we delve into the application of cosmological diagnostic tools, specifically the statefinder and the $Om(z)$ diagnostics. Both of these tools align with our previous conclusions, confirming the phantom-like behavior exhibited by our cosmological model. These results collectively contribute to our understanding of the dynamic interplay between gravity, dark energy, and the expanding cosmos.

Progress of Theoretical and Experimental Physics accepted version

References in corpus (23)

• Raising the bar: new constraints on the Hubble parameter with cosmic chronometers at z$\sim$2
• Cosmic Distances Calibrated to 1% Precision with Gaia EDR3 Parallaxes and Hubble Space Telescope Photometry of 75 Milky Way Cepheids Confirm Tension with LambdaCDM
• Two new diagnostics of dark energy
• Large Scale Structure as a Probe of Gravitational Slip
• Cosmological solutions and growth index of matter perturbations in $f(Q)$ gravity
• The Newtonian Limit of F(R) gravity
• A parametric model for dark energy
• Energy Conditions in $f(Q)$ gravity
• Accelerated Expansion of the Universe in Non-minimally Coupled Gravity
• Cosmography in $f(Q)$ gravity
• Cosmic acceleration with bulk viscosity in modified $f(Q)$ gravity
• Anisotropic nature of space-time in $f(Q)$ gravity
• Three thermodynamically-based parametrizations of the deceleration parameter
• Observational constraints on two cosmological models of $f(Q)$ theory
• Cosmic acceleration and energy conditions in $\Lambda$CDM symmetric teleparallel $f(Q)$ gravity
• Late-time acceleration in $f\left(Q\right)$ gravity: Analysis and constraints in an anisotropic background
• A New Equation of State for Dark Energy Model
• Model parameters in the context of late time cosmic acceleration in $f(Q,T)$ gravity
• Interacting 3-form dark energy models: distinguishing interactions and avoiding the Little Sibling of the Big Rip
• Dark matter-dark energy interaction for a time-dependent equation of state
• Holographic dark energy in Gauss-Bonnet gravity with Granda-Oliveros cut-off
• Stability analysis of anisotropic Bianchi type-I cosmological model in teleparallel gravity
• Phenomenological Reconstruction of $f(T)$ Teleparallel Gravity

Cited by in corpus (7)

• DESI DR2 Results II: Measurements of Baryon Acoustic Oscillations and Cosmological Constraints
• Gravitational tensor and scalar modes in $f(Q,B)$ non-metric gravity
• Cosmological dynamics and observational constraints on a viable $f(Q)$ non-metric gravity model
• A short review on Quintom dark energy theory
• Observational constraints on cosmological parameters in the Bianchi type III Universe with f(R,T) gravity theory
• Charged Gravastar Solutions in the Finch-Skea Framework with f(\mathbb{Q}) Gravity
• Phase space analysis of Bianchi III Universe with $f(R,T)$ gravity theory