Research Interests

In June of 2009, I received my PhD from Stanford University, under the guidance of Dr. Tom Abel, with a thesis entitled "The Formation of Primordial Protostars."  While I was there, I was a member of the Kavli Institute for Particle Astrophysics and Cosmology.  Since then, I held postdoctoral positions at UCSD and Columbia, and Research Scientist positions at Columbia and now the National Center for Supercomputing Applications.

I run ab initio cosmological simulations of the early universe.  The simulations are initialized from a random realization of the universe shortly after the big bang, and relatively simple principles of physics govern the dynamics and evolution of the gas and dark matter.  From these simple rules and laws, complicated and often beautiful objects form -- and I study the manner in which the first stars in the universe form in these simulations.  For the most part, these stars seem to be lone giants, forming a single massive star at a time, living for but a brief moment, and then enriching their surroundings with heavy elements.  The image on the left is of a calculation where we actually saw two stars form in a single primordial cloud.

These simulations are done using the code Enzo, which implements Adaptive Mesh Refinement hydrodynamics. We run at extremely high resolutions -- in simulations on the scale of kiloparsecs, like what I run, we can resolve all the way down to within the radius of the Earth! (In one particular simulation, the smallest cell size was just under 200 miles!) We utilize supercomputing resources for this task, and we have a suite of software for both visualizing and analyzing the results.

I am very interested in extending the physical model of our simulations by adding new and more realistic physics.  Additionally, pushing our calculations to higher and higher resolution is a top priority. I am very interested in examining all aspects of these first structures -- their formation, evolution, death, and the manner in which they enrich the surrounding media, ultimately leading to further generations of objects.

Please feel free to email me if you're interested in what I work on!