Abstract Details
| Name: Yashi Tiwari Affiliation: Indian Institute of Science Conference ID: ASI2024_217 Title : Towards a possible solution to the Hubble tension with Horndeski gravity Authors and Co-Authors : Yashi Tiwari 1, Basundhara Ghosh 2, Rajeev Kumar Jain 2 Abstract Type : Poster Abstract Category : Galaxies and Cosmology Abstract : The Hubble tension refers to the discrepancy in the value of the Hubble constant $H_0$ inferred from the cosmic microwave background observations, assuming the concordance $\Lambda$CDM model of the Universe, and that from the distance ladder and other direct measurements. In order to alleviate this tension, we construct a plausible dark energy scenario, within the framework of Horndeski gravity which is one of the most general scalar-tensor theories yielding second-order equations. In our set-up, we include the self-interactions and nonminimal coupling of the dynamical dark energy scalar field which enable very interesting dynamics leading to a phantom behaviour at low redshifts along with negative dark energy densities at high redshifts. These two features together make this model a promising scenario to alleviate the Hubble tension for appropriate choices of the model parameters. Finally, as a consistency check, we show that this setup is also free from both the gradient and ghost instabilities. |