Broadly I am interested in understanding various physical implications of quantum gravitational nature of spacetime in cosmological and black hole spacetimes. My research focuses on answering questions concerning the fate of cosmological and black hole singularities, physics of quantum gravity in the very early universe and exploring its potential signatures using cosmic microwave background (CMB), using a combination of analytical and high performance computational methods.
One of the areas I work on is loop quantum cosmology (LQC) where the main result is that big bang singularity is resolved by quantum geometry effects and is replaced by a big bounce. Since we found this result in 2005-06, dozens of groups around the world have studied big bounce in LQC in different spacetimes including anisotropic models and in presence of inhomogenities. There is a lot of ongoing work on understanding its physical implications in the very early universe and in black hole spacetimes. My current research focuses on: How robust is the big bounce and the resulting physics? How do we obtain these results directly from loop quantum gravity? What are the unique phenomenological signatures of LQC and related models in CMB? How do we tackle foundational questions about the problem of time and the choice of clocks and what are their phenomenological implications? How do we extract consistent probabilities in closed systems such as our Universe? How does physics from quantum geometry alleviate problems of models of very early universe including inflation and its alternatives? What are the implications of quantum geometry for black holes?
These are selected publications in a reverse chronological order. For a complete list please visit Inspire or Google scholar links on this page.
These are selected media highlights featuring my research
I serve as an editor of International Journal of Modern Physics D (since 2010) and Associate Editor of Universe (since 2021). I served as an editor of Classical and Quantum Gravity from 2012-2021.
Some of the committees I serve on include
I have taught courses at various levels in LSU. These include under-grad mechanics and quantum mechanics, grad mechanics, grad computational physics, and particle mechanics. I also designed an AdS/CFT course for grad students. In addition, I gave a cosmology course (with Niayesh Afshordi and Hiranya Peiris) and an advanced course on cosmological perturbations (with Neil Turok) at Perimeter Institute Scholars program. I also taught a cosmology course at Penn State.
Links refer to co-authored published papers.
I was born in New Delhi, India where I completed my Bachelors and Masters in Physics from S. G. T. B. Khalsa College, University of Delhi. I did my PhD with Naresh Dadhich from Inter-University Center for Astronomy and Astrophysics at Pune, India in 2004. I was then a postdoc at the Penn State with Abhay Ashtekar and a Distinguished Postdoc Researcher at the Perimeter Institute. I joined LSU as an Asst. Professor in 2010.