I'm an Associate Professor in the Physics Department at the University of Florida. My research focuses on a range of problems in supermassive black hole and galaxy evolution, including black hole formation and evolution, the role of galaxy mergers, signatures of black hole inspiral and merger, and gravitational wave sources. I specialize in numerical simulations with an emphasis on direct comparisons to observations.
Formation & Evolution of SMBHs and Galaxies
Broady, I am interested in the interplay between SMBHs and their host galaxies in a range of environments and cosmic epochs. In particular, we are studying the origins and early growth of SMBHs, the role of galaxy mergers in producing the observed correlations between SMBH mass and galaxy bulges, and the demographics of the intermediate-mass BH (IMBH) population. The recently launched James Webb Space Telescope (JWST) has already provided an abundance of new insight about the early Universe!
AGN Fueling & Feedback
My group uses hydrodynamics simulations to study the mechanisms for fueling active galactic nuclei (AGN, or accreting SMBHs), as well as the feedback imparted to galaxies by these highly energetic sources. We also study the role of galaxy mergers in triggering AGN, as well as methods for finding dual AGN and for characterizing the effects of obscuration and other selection bias in AGN observations.
Binary SMBH Inspiral and Gravitational Waves
Galaxy mergers are also of great interest because they lead to the formation of SMBH binaries, which are powerful sources of gravitational waves (GWs). These low-frequency gravitational waves could be detected in the coming years with pulsar timing arrays and with a space-borne laser interferometer (LISA). I am a Full Member of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) pulsar timing collaboration and an Associate Member of the LISA Consortium. My group is working to constrain the uncertain timescales for binary SMBH inspiral and the resulting GW source populations.
When two black holes merge, asymmetry in their gravitational wave emission imparts a "recoil kick" to the merged black hole, which can in some cases eject a SMBH from its host galaxy entirely. In addition, if two black holes stall during their inspiral, a third SMBH may enter the system in the meantime. Three-body SMBH interactions can hasten SMBH mergers, affecting GW event rates, and they can also cause a "slingshot recoil" of the lightest SMBH from the system. I've also developed models for the observable signatures of recoiling AGN, and we are involved in ongoing campaigns to search for and confirm candidate recoils. My group studies all of these processes, and we are also investigating new methods for modeling SMBH dynamics in large-scale simulations.