Rakesh Kumar Sivakumar - Dark Matter From Modified Gravity and Extra Dimension.

Abstract: Gravitational interactions may be the only forces to which dark matter (DM) responds. This makes gravity a particularly intriguing arena for understanding DM as well as physics beyond the Standard Model (SM). In this talk, I will mainly discuss two manifestations of gravitational interactions.

(i) Theories beyond Einstein gravity can naturally give rise to a spin-0 DM candidate that emerges purely from spacetime geometry. I will show how the freeze-in mechanism can yield the correct relic abundance for such a candidate, considering models of f(R) gravity, while remaining consistent with experimental bounds from searches for DM decay signatures.

(ii) I will then demonstrate how gravity alone can serve as a portal to address the baryon–DM coincidence problem, while simultaneously solving the hierarchy problem within the Randall–Sundrum framework.

Finally, I will briefly discuss the role of recent LHAASO observations in placing constraints on gravitationally produced DM, and on the maximum temperature attained during the earliest epoch of our Universe.

Видео Rakesh Kumar Sivakumar - Dark Matter From Modified Gravity and Extra Dimension. канала Research Talks (from Home)