Video Lectures

Despite the remarkable success of the standard model of cosmology, the lambda CDM model, at predicting the observed structure of the universe over many scales, very little is known about the fundamental nature of its principal constituents: dark...

All large-scale structure cosmologists are faced with the question: how do we robustly extract cosmological information, such as on dark energy, gravity, and inflation, from observed tracers such as galaxies whose astrophysics is extremely complex...

The albedo of a celestial body is the fraction of incident starlight reflected by it. The study of the albedos of Solar System objects is at least a century old, at least in the Western world. As examples: Bond (1861) speculated on the near-unity...

Planets form from disks of dust and gas surrounding young stars.  As they grow, these new planets inherit their chemical composition from the surrounding material and then sculpt it through gravitational interactions to form gaps and other...

I will weave three separate threads. The first will be to describe recent and ongoing results from the Dark Energy Spectroscopic Survey. I will present the BAO results from the early DESI data, and some of the preparatory work for the Year 1 data. I...

Instantons are an important source of nonperturbative effects in quantum field theories, but their role in asymptotically free theories has not been well understood. In this talk, we will present a new approach to instanton analysis in the context...

The iconic spiral arms that decorate the disks of massive galaxies (like our own Milky Way) have been studied observationally and theoretically since they were first recorded 180 years ago, nevertheless the exact details of their nature remains...

I will talk about the invariants of topologically ordered states of quantum lattice systems that generalize Berry classes and can be defined for any gapped state in any dimension. The equivariant version of such invariants unifies and generalizes...

Charge-exchange (CX) collisions of the solar wind (SW) high-ionization-state minor ions with LISM neutrals are responsible for much of X-ray production in the outer heliosphere. In this talk, we discuss numerical modeling of the heliospheric CX X...

Kinematically, massless particles in Lorentz-invariant theories are classified by a dimensionful "spin scale"ρ  (2nd Casimir invariant) that characterizes helicity states' mixing under little group transformations.  However, dynamics for particles...