About

I am an STFC Ernest Rutherford Fellow at the Institute of Cosmology and Gravitation at the University of Portsmouth. I study the properties of dark energy, dark matter and gravity using data on the large-scale structure of the Universe gathered by galaxy surveys on the world’s leading telescopes.

My background

I grew up in Delhi, India, where I did my undergraduate degree at the University of Delhi. I won a Rhodes Scholarship to the University of Oxford in 2005, where I took an MPhys degree at Trinity College. I then held a Clarendon Domus scholarship during my DPhil (PhD). I held short postdoctoral positions at the University of Bielefeld and the University of Helsinki before taking up a Marie Skłodowska-Curie Individual Fellowship and the Dennis Sciama Fellowship at the ICG in Portsmouth. I then moved to UCL before returning to Portsmouth in 2022.

My research

My research covers theory, simulation and observational cosmology, with a focus on methods of analysing galaxy survey data to understand the effects of dark energy and dark matter in the Universe. I use a combination of many techniques to achieve this, including redshift-space distortions, baryon acoustic oscillations, gravitational lensing and secondary CMB anisotropies. I am particularly interested in the use of cosmic voids – low-density regions identified in 3D maps of the galaxy distribution – as exciting tools to enhance the effectiveness of all these analyses. I also work on models of decaying dark matter and inflation in the early Universe.

I am a member of several international survey collaborations:

  • ESA Euclid Consortium
  • the Dark Energy Spectroscopic Instrument (DESI) survey
  • the extended Baryon Oscillation Spectroscopic Survey (eBOSS), part of the Sloan Digital Sky Survey (SDSS-IV)
  • the Dark Energy Survey (DES)

Other interests

I am a keen hiker, mountaineer and climber. While at Oxford I served as both Secretary and Treasurer of the OUMC, and I have climbed, organised expeditions and recorded occasional first ascents in the Indian Himalaya, the Alps, the Dolomites, the Moroccan Anti-Atlas, and the Pyrenees. I am a keen squash player, and have played club cricket in 3 different countries (can you guess which three?).