Joint IAS Princeton University Astrophysics Colloquium

The NASA Kepler Mission has demonstrated that planets with radii larger than Earth yet smaller than Neptune are common around Sun-like stars. Although Kepler has determined the physical sizes of hundreds of such planets, we know virtually nothing...

Hydrogen recombination at redshifts z ~ 1100 - 1500 leads to the rapid decrease of the optical depth of the Universe due to Thomson scattering. As a result CMB photons previously strongly coupled with baryonic matter become free and able to reach...

Galaxies mark the nexus between the "micro" scales of individual stars and black holes, and the "macro" scales of the "cosmic web", the large scale structure in which galaxies are embedded. Modeling the physics of galaxy formation is therefore one...

Intrinsic alignments of galaxy shapes with cosmological large-scale structure include a great deal of information about galaxy formation and evolution in a cosmological context, while also serving as a contaminant to weak gravitational lensing...

Note: Video recording will be available at https://www.ias.edu/video/sns.

The physical mechanism behind the acceleration of the universe remains one of the great mysteries of modern cosmology. Given the proliferation of dark energy models on the market, an obvious question is: How can we rule out whole classes of dark...

Infrared observations from Spitzer Space Telescope and Herschel Space Observatory are used to study the interstellar dust in M31. A physical dust model is used to map the dust surface density, dust/gas ratio, starlight heating intensity, and the...

The advent of wide-field synoptic imaging has re-invigorated the venerable field of time domain astronomy. Our framework of optical transients no longer has a wide six-magnitude luminosity "gap" between the brightest novae and faintest supernovae...

A classic problem posed by long gamma ray bursts (GRB) is that the energy output requires gravitational energy release so deep within the host star that the prompt gamma rays should, upon naive consideration, have been obscured. It is suggested that...