I am a Marie Curie Research Fellow (2015-2017) and Dennis Sciama Fellow (2015-2018) at the Institute of Cosmology and Gravitation at the University of Portsmouth. My research aims to understand the contents, origin, and evolution of the Universe.

I previously held postdoctoral positions at the University of Helsinki (as an associate of the Helsinki Institute of Physics), and at the University of Bielefeld. I completed my DPhil in Theoretical Physics at Merton College Oxford in 2011, under the supervision of Subir Sarkar. Before that I was a Rhodes Scholar at Trinity College Oxford, where I read for an MPhys degree. I also have a B.Sc. Hons. in Physics from the University of Delhi.

An old PDF version of my CV (from January 2015) is available here.


I study the large-scale structure of the Universe, in particular inhomogeneities and rare fluctuations in the distribution of galaxies. In particular I am interested in 'cosmic voids' — large underdensities which may provide sensitive tests of a range of exciting cosmological models. I have compiled public catalogues of voids drawn from large galaxy redshift surveys: to access these please go here.

I also work on aspects of the cosmic microwave background and the integrated Sachs-Wolfe effect, and on building and testing models of inflation.


You can get an up-to-date list of my publications from: arXiv, ADS, INSPIRE.


In addition to academic research, I write a sporadic blog about physics and astronomy at Blank On The Map. I often try to give layman-level summaries of my own research and other news here.

Other activities

Outside physics, I am a rock climber and mountaineer. With friends from the OUMC and elsewhere I have climbed routes all over the UK and in northern Germany, the Alps, the Dolomites, the Moroccan Anti-Atlas and in the Indian and Nepali Himalayas. Some of these were first ascents.