I am a cosmologist. I study the fossilized heat of the Big Bang, the cosmic microwave background (CMB) for clues about the physics that governed the very early universe. About 1% of the snow picked up by an untuned television arises from this radiation, generated when the universe was just 0.01% of its present age.

I also enjoy thinking about galaxy evolution, stellar dynamics, and the structure of the Milky Way.

The portrait above was taken by Max Alexander for the Explorers of the Universe exhibition as part of the International Year of Astronomy 2009.

BIO:

I am a Reader in Astronomy in the Astrophysics Group in the Dept. of Physics and Astronomy at UCL. I am also the coordinator of the CosmicDawn project, funded by the European Research Council under the FP7 Ideas programme.

Prior to becoming a Lecturer in Cosmology at UCL in 2009, I was an STFC Advanced Fellow at the Institute of Astronomy, University of Cambridge and a Junior Research Fellow at King's College Cambridge. Previously, I was a Hubble Fellow in the Kavli Institute for Cosmological Physics at the University of Chicago. I did my postgraduate research at the Department of Astrophysical Sciences at Princeton University. I was an undergraduate at the University of Cambridge, where I was a member of New Hall. I was born in Sri Lanka, a beautiful island in the Indian Ocean.

From 2001-2006 I was a member of the WMAP Collaboration. The CMB data from the Wilkinson Microwave Anisotropy Probe (WMAP) formed the foundation for the era of precision cosmology, and dramatically improved our understanding of the basic characteristics of the Universe (its contents, history, expansion rate and eventual fate).

I am currently a member of the Planck Collaboration. Planck, an ESA satellite, is the successor to WMAP. It is currently mapping the primordial fluctuations in the microwave sky at the distant second Lagrange point of the Sun-Earth system, 1.5 million km away.

DOWNLOADS:

My Ph.D. thesis (Princeton, 2003, advisor Prof. D. Spergel) involved the cosmological analysis and interpretation of the WMAP first year data. You can download the chapters here:

[chap0.pdf] [chap1.pdf] [chap2.pdf] [chap3.pdf] [chap4.pdf] [chap5.pdf]

ModeCode: Bayesian Parameter Estimation for Inflation

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