arXiv:2409.17193v1 Announce Type: new
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.
In this study, the authors investigate the cosmic evolution of the Universe using the exponential Weyl-type $f(Q, T)$ gravity model. They employ a dynamical system approach, deriving a system of linear differential equations and identifying critical points corresponding to different cosmological epochs.
By analyzing the theoretical predictions, the researchers find a transition from a deceleration phase to an acceleration phase, with stable and unstable critical points characterizing different phases of the evolution. To validate their findings, they use observational data from Cosmic Chronometers ($CC$) and $Pantheon^+$ datasets.
Using the observational data, the authors constrain the Hubble parameter and analyze other cosmological and geometrical parameters. These analyses confirm the transition from deceleration to acceleration, with the equation of state (EoS) parameter approaching $Lambda$CDM at late times.
To further validate their results, the authors present the behavior of the state finder pair. They obtain an age of the Universe of .81$ Gyr according to the $CC$ data and .96$ Gyr with the $Pantheon^+$ dataset. The model’s behavior in both approaches shows strong agreement in the late-time behavior of the Universe, reinforcing the reliability of the Weyl-type $f(Q, T)$ gravity model in describing the expansion history of the Universe.
Future Roadmap
Challenges
- One of the potential challenges that researchers may face is obtaining more precise observational data. The accuracy of the model’s predictions heavily relies on the quality and quantity of the data used for validation.
- Further investigation is needed to explore the limitations of the Weyl-type $f(Q, T)$ gravity model and its applicability beyond the current observations. This will require more advanced theoretical analyses and simulations.
- Understanding the physical interpretation of the critical points identified in the dynamical system approach is another challenge that researchers might encounter. Elucidating the implications of these critical points could provide deeper insights into the cosmic evolution.
Opportunities
- As new observational techniques and instruments are developed, researchers will have the opportunity to collect more precise and extensive data sets. This will enable more accurate validation of the Weyl-type $f(Q, T)$ gravity model and potentially uncover new phenomena in the cosmic evolution.
- Exploring alternative gravity models and comparing them with the Weyl-type $f(Q, T)$ model could provide valuable insights into the nature of the Universe’s expansion. This could open up new avenues for understanding fundamental physics and the nature of dark energy.
- Collaboration between theorists and experimentalists will be crucial in advancing our understanding of the cosmic evolution. By combining theoretical analyses with cutting-edge observations, researchers can refine and improve the models, leading to a more comprehensive understanding of the Universe.
Conclusion
This study highlights the cosmic evolution of the Universe using the exponential Weyl-type $f(Q, T)$ gravity model. The theoretical analysis and observational data validation both confirm a transition from a deceleration phase to an acceleration phase. The model’s agreement with the late-time behavior of the Universe, as well as the obtained age estimates, reinforce the reliability of the Weyl-type $f(Q, T)$ gravity model. However, further investigations, improvements in observational data, and collaboration between different branches of physics are necessary to overcome challenges and unlock new opportunities for understanding the cosmic evolution.