Astrophysics

Weak gravitational lensing by the intervening large-scale structure (LSS) of the Universe is the leading non-linear effect on the anisotropies of the cosmic microwave background (CMB). The integrated line-of-sight mass that causes the distortion --...

Abstract: I will discuss a direct rigorous mathematical proof of the Gregory--Laflamme instability for the 5D Schwarzschild black string. This is a mode instability at the level of the linearised vacuum Einstein equation. Under a choice of ansatz...

Debris disks provide exciting opportunities to study planet formation through the composition and architecture of planetary building blocks. The Spitzer Space Telescope Infrared Spectrograph (IRS)’s comprehensive survey of more than 500 debris disks...

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...

Phenomenological parameterization of the perturbed Einstein's equations has become an important route to testing General Relativity (GR) at cosmological scales. This is often done by constraining a pair of modified gravity (MG) parameters. We...

Resolved stars serve as versatile, plentiful tracers of the baryonic content of galaxies. By exploiting the precise, high-dimensional information provided by multi-band imaging of stars, we may place quantitative constraints on fundamental questions...

Rotationally supported, cold, gaseous disks are ubiquitous in astrophysics and appear in a diverse set of systems, such as protoplanetary disks, accretion disks around black holes, or large spiral galaxies. By using a cold, two-dimensional, gaseous...

Misaligned disks in binaries were commonly thought to evolve to a coplanar
state. However, recent theory and observations have surprisingly shown that disks around
eccentric orbit binaries can evolve to a polar state in which the disk is...