I am a theoretical/computational astrophysicist and cosmologist. Using the world’s most powerful supercomputers, I generate cosmological simulations to model the formation of cosmic structures, including galaxies and their stars. My group uses these simulations as theoretical laboratories to develop models of galaxy formation, star formation, stellar nucleosynthesis, and the nature of dark matter. We are particularly interested in understanding our own Milky Way galaxy. The movie above flies through one of my Latte simulations of a galaxy like the Milky Way, showing its evolution over the last billion years.
cosmological structure formation
We model the formation of dark-matter + gaseous halos, and the galaxies that form inside them, including the physics of dark matter, gas dynamics, star formation, stellar evolution, and stellar feedback. We seek to understand the many components of galactic ecosystems: their dark-matter halos, stellar and gaseous disks, giant molecular clouds, star clusters, and stellar halos.
We model the formation history of our Milky Way galaxy, the Andromeda (M31) galaxy, and our Local Group of low-mass galaxies. We use our simulations as theoretical laboratories for ‘galactic archeology’: to translate our observations of these galaxies today into understanding their formation histories across cosmic time.
We model the dynamics of stars and gas to measure the spatial and velocity distribution of dark matter around the Milky Way and nearby galaxies, with the ultimate goal of testing the particle nature of dark matter.
FIRE simulation project
We are members and developers of the Feedback In Realistic Environments (FIRE) simulation project. FIRE is pushing the resolution frontier in cosmological simulations of galaxies, using the zoom-in technique to pursue a ‘bottom-up’ approach, resolving key components of the multiphase interstellar medium and stellar evolution, all within a cosmological context. Thus, we seek to improve the predictive power of models for galaxy formation and connect them to underlying stellar populations.
Latte simulations of Milky Way-like galaxies
Within the FIRE collaboration, I am leading the Latte suite of simulations of Milky Way-like galaxies, to understand the formation of our own Milky Way galaxy in a cosmological context. The movie above flies through a Latte simulation, showing its evolution over the last 1 billion years.
connections with observations
While my group’s research is primarily theoretical, we also emphasize close connections with astronomical observations. I am co-leading the MW-6D and M31-6D surveys, two Treasury Programs using the Hubble Space Telescope to measure full 6-D orbital phase-space and star-formation histories for all of the satellite galaxies around the Milky Way and Andromeda (M31).
We are grateful for grant funding support from
National Aeronautics and Space Administration (NASA)
Space Telescope Science Institute (STScI)
National Science Foundation (NSF)
Society of Hellman Fellows
Texas Advanced Computing Center