Tracing cosmic evolution through Weyl-Type f(Q,T) gravity model: theoretical analysis and observational validation

TL;DR

This paper explores a Weyl-type f(Q,T) gravity model to describe cosmic evolution, analyzing its theoretical dynamics and validating predictions with observational data, confirming the universe's transition from deceleration to acceleration.

Contribution

It introduces a novel Weyl-type f(Q,T) gravity model and combines dynamical system analysis with observational validation to explain cosmic evolution.

Findings

Transition from deceleration to acceleration confirmed

Universe's age estimated around 13.8-13.96 Gyr

Model aligns with late-time ΛCDM behavior

Abstract

We investigate the cosmic evolution of the Universe across different cosmological epochs in exponential Weyl-type $f(Q, T)$ gravity model. The theoretical analysis involves a detailed dynamical system approach, where we define dimensionless variables and derive a system of linear differential equations to identify critical points corresponding to the radiation, matter and de Siter phase. The findings show the transition from deceleration to acceleration phase, with stable and unstable critical points characterizing different phases of the evolution. In the second approach, we validate the theoretical predictions by using observational data from Cosmic Chronometers ($CC$) and $Pantheon^+$ datasets. We constrain the Hubble parameter and subsequently analysed the other cosmological and geometrical parameters. In this approach also, the transition from deceleration to acceleration has been confirmed, with the equation of state (EoS) parameter approaching $\Lambda$CDM at late times. The further validate this, we present the behaviour of state finder pair. We obtain the age of the Universe $13.81$ Gyr according to $CC$ data and $13.96$ Gyr with the $Pantheon^+$ dataset. The model behaviour in both the approaches shows strong agreement in the late-time behavior of the Universe. The evolutionary behaviour of Hubble parameter and distance modulus, reinforcing the reliability of the Weyl-type $f(Q, T)$ gravity model in describing the expansion history of Universe.