Abstract: Neutron stars are physicists' dreams come true: they bring together aspects of classical and quantum electrodynamics, coupled with strongly magnetized plasma physics in the curved rotating spacetime of a massive compact object. They are observed to be powerful emitters of non-thermal electromagnetic radiation, spanning about 20 orders of magnitude in photon energy, from radio waves to multi-TeV gamma-rays. Understanding these diverse emission signatures requires modeling the complex dynamics of radiating relativistic plasmas, which occur across vastly different time and spatial scales. In this talk, I will explore how modern computational techniques now enable accurate simulations of these plasmas, facilitating direct comparisons with observational data. I will highlight simulations of pair production discharges and radiative magnetic reconnection, discussing their crucial role in powering pulsars’ multi-wavelength non-thermal radiation. I will finish by discussing the frontiers of studying plasmas around magnetars -- neutron stars possessing the strongest magnetic fields in the Universe --which can also be powering at least some of the enigmatic Fast Radio Bursts.

Bio: Sasha Philippov graduated with a M.S. in "applied physics and mathematics" with highest honors from the Moscow Institute of Physics and Technology in 2012 and received his Ph.D. in Astrophysical Sciences from Princeton University in 2017. He works on the theory and modeling of plasmas around black holes and neutron stars. Recent focus of the group was on understanding (a) mechanisms of coherent radio emission from neutron stars (including Fast Radio Bursts); (b) flares from accreting black holes and merging neutron stars, (c) particle acceleration in black hole-powered jets. These ongoing efforts contribute to interpreting the observed signatures of black holes and neutron stars using first-principles physics.