Upcoming Seminar

Date :  26th November 2025

Time: 03:30 P.M - 04:30 P.M

Title:  Inflation in scale-invariant quadratic gravity

Speaker: Debangshu Mukherjee

Postdoctoral Fellow,

Dept. of Physics, POSTECH,

South Korea

Abstract: We will discuss a specific scale-invariant model of quadratic gravity with a non-minimally coupled scalar filed. We will discuss inflation in such a model wherein Planck mass is generated classically by a scalar field which evolves from an unstable fixed point to a stable fixed one thus braking scale-invariance in the process. The dynamics will be discussed employing standard dynamical system techniques. Spectral index and power spectrum for tensor perturbations of this model will be compared with data to put constraints on the dimensionless parameters of the model which is expected to be within range of future CMB missions like CMB-S4, LiteBIRD and STPol. We will also briefly look at the possibility of generation of primordial magnetic fields during inflation. This talk will be based on a couple of works https://arxiv.org/abs/2205.06475 & https://arxiv.org/abs/2303.16107 done in collaboration with Chiara Cecchini, Anish Ghosal and Massimiliano Rinaldi.

Meeting Link: https://meet.google.com/vjs-pgwq-ros