Director, Franke Program in Science and the Humanities, Yale University
My research interests in black hole physics are focused the formation, fueling and feedback from supermassive black holes over cosmic time. I develop empirically motivated models for understanding the growth and evolution of black hole populations with a view to integrating fundamental physical processes that operate over a range of scales from sub-pc to Mpc, that are relevant to the physics of accretion, including angular momentum transfer and the alignment of spins. Having proposed several new channels for the formation of seed black holes and intermediate mass black holes that include direct collapse of pristine gas-disks and amplified growth in the dense gas-rich environments of nuclear star clusters, I work on predictions of multi-wavelength observational signatures of these processes. One key motivation is to probe the underlying deeper correlation between parent dark matter halos, host galaxies and central black holes that drives their observed co-evolution that includes energy input from the accreting black hole and physical processes that couple small and large scales; quasar outflows. Our recent work analyzing cosmological simulations has revealed the potential existence of an entirely new population of wandering supermassive black holes. I am also interested in the role of gas and accretion disks in effecting binary black hole mergers in gas-rich galaxy cores; the electro-magnetic and gravitational wave signatures from these systems; the evolution of eccentricity in binary black hole mergers; and their multi-messenger signatures - - gravitational waves and accompanying electromagnetic counter-parts.
Deeply invested in interdisciplinary scholarship, I am interested in foundational questions in epistemology – nature of knowledge production and inference in science in the absence of controlled experiments; the nature of causation, correlation and the role of models and simulations in inference.With undergraduate degrees in Physics and Mathematics and graduate study in the history and philosophy of science from the Program in Science, Technology & Society at M.I.T, I completed my PhD at the Institute of Astronomy at Cambridge University where I was a fellow of Trinity College. I am currently on the faculty at Yale with joint appointments in the Departments of Astronomy & Physics, where I also serve as the Director of the Franke Program in Science and the Humanities.