Astrophysics

The high and dry desert of the Chilean Andes is a magnificent site from which to observe the universe.  The Atacama Cosmology Telescope (ACT) made measurements of the cosmic microwave background (CMB) from there for fifteen years, with a series of...

The fundamental natures of dark energy and dark matter remain two of the biggest mysteries in modern cosmology. We show that a simple coupling between dark energy and dark matter can simultaneously address two distinct hints at new physics coming...

Abstract: We establish local well-posedness for the Einstein-Euler system with a physical vacuum boundary in spherical symmetry. Our proof relies on a new way of thinking about Einstein’s equations in spherical symmetry that is well-adapted to the...

Each week, we hold a relatively informal seminar/discussion series with an emphasis on extra-galactic and large-scale structure astrophysics.

During Galread a leader/visitor presents a recent paper to the discussion group. The PDF of the paper is...

Since its launch just two and a half years ago, JWST has made multiple remarkable discoveries. I will discuss the search for ever more distant galaxies and accreting black holes, and the implications of these observations for our theories of...