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 general
relativity in pursuit of a deeper understanding. In our analysis, we delve into the recently
proposed modified f(Q) gravity, where Q represents the nonmetricity scalar responsible for
gravitational effects. Specifically, we investigate a cosmological model characterized by the
functional form f(Q) = Q + αQn, where α (with α = 0) and n serve asfree 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.
