My current primary research focus is on the data analysis of multi-frequency microwave sky maps such as are from the WMAP satellite and are to come from the Planck satellite, along with ancillary data. In principle we can find out an awful lot about the universe by carefully studying the intensity and polarization of the cosmic microwave background (CMB) radiation reaching us today. Unfortunately there are some complications, a major one (particularly for polarization) being contamination from "foreground" signals, typically from the galaxy. The hope is that these signals have different spectral and spatial correlation properties than the CMB, enabling us to extract the cosmological information nontheless. I am trying to come up with ways to do this and to fold in our incomplete knowledge of the foregrounds and their properties into uncertainties on cosmological predictions.
I have done work on quantum cosmology, inflation and the landscape measure problem and continue to think about such matters. I am currently looking again at eternal inflation from a novel standpoint, partially inspired by a minigrant from the Foundational Questions Institute. This minigrant has enabled me to begin to investigate doing computing for cosmology on graphics cards; click below for more details...
Information on Graphics Card Computing for Cosmology.