Since 2008 I’ve been working in theoretical astrophysics with Roger Blandford. Astrophysics is a great field to study because of the diversity and the scale of the phenomena in our universe. The universe is a laboratory for extreme physics beyond anything we can create on Earth: extreme gravity around black holes, extreme electrodynamics around neutron stars, and cosmic rays with ten million times more energy than our best machines.
I study cosmic rays, high-energy particles streaming through space nearly at the speed of light. Nature finds a way to accelerate these particles to higher energies up to and beyond anything humans can do on Earth. We’ve known about these particles for over a hundred years, but we still haven’t figured out the whole story of exactly how and where these particles are accelerated.
My collaborators and I are developing a model where the highest-energy cosmic rays come from the giant accretion shocks around the large-scale structure of galaxies, which can be seen in the figure to the right, a temperature map from a cosmological hydrodynamic simulation from Kirk Barrow.
I have also worked on Galactic cosmic rays from supernova remnants, the giant shockwaves from exploding stars. These shockwaves travel at thousands of kilometers per second and accelerate cosmic rays in our galaxy, but these shocks cannot create the highest-energy cosmic rays we’ve observed.
