Speaker
Description
The LCDM model has long served as the cornerstone of modern cosmology, successfully explaining a wide range of observations. However, with the advent of precision cosmology, emerging discrepancies among key parameters have highlighted its limitations in comprehensively describing the universe’s evolution. To address these challenges, my research explores interacting dark sector models, investigating the capabilities of interacting dark energy as an alternative framework to alleviate the persistent H0 and S8 tensions in cosmology. In this talk, I will present the development of the background and perturbation evolution equations for an interaction model of dark matter and quintessence dark energy. I will further discuss the model’s analysis using a combination of low- and high-redshift observational datasets. Given the uncertainties in both the physics of dark energy and current observational measurements, our results reveal a dataset-dependent variation in the mean value and constraining power of the Hubble constant, H0. By allowing the interaction parameter to evolve freely, the analysis indicates that although the interaction strength remains small, it is not disfavoured by the data at late times. Additionally, I will compare the results obtained under the assumption of spatial flatness with those derived within the framework of a curved geometry (Coupled+Omega_k model). This comparison provides insights into the role of spatial curvature in addressing the ongoing H0 and S8 tensions. I will delve deeper into how these findings within the Coupled+Omega_k picture suggest that relaxing the flatness assumption in coupled dark sector models leads to more precise constraints on both H0 and S8.
