TITLE
The general relativistic Poynting-Robertson effect in radiation processes
ABSTRACT
In this talk, I introduce the general relativistic model of the Poynting-Robertson effect in 2-dimensions, following the relativity of observer splitting formalism. This effect configures to be a viscous force, manifesting itself through the radiation drag force, which removes energy and angular momentum from the affected matter. I analyse, for the first time, such effect in the Lagrangian formalism, not typical for a viscous system in General Relativity. I show some particle orbits in Schwarzschild and Kerr spacetimes. I extend further this model in 3-dimensions, which leads to interesting results. Also in this case, I show some particle orbits in Schwarzschild and Kerr metric. As an astrophysical application, I present a numerical model for studying the evolution of a thin accretion disc around a central rotating black hole/neutron star and invested by a constant/variable radiation field in 2-dimensions. I report some numerical simulations, useful both to explain some puzzling observations and to visualise the dynamical evolution of the disc structure around a compact object.