C10 Q40, Theoretical Astrophysics
Auf der Morgenstelle 10
Tuebingen, Germany 72076


I am primarily interested in black holes and their highly energetic neighborhoods. I study them using x-rays and gravitational waves. Check out Research Interests for details.

My secondary interests include science outreach, linguistics, history and philosophy.

My hobbies include exploring new places, new culture and new food.

Personal data

2010 BSc in Physics (CMI, India)
2012 MS in Physics (UT Brownsville, Texas, US)
2015 PhD in Physics (UT San Antonio, Texas, US)
2015 Postdoc, Fudan University (Shanghai)
2017 Young Researcher (Tuebingen, Germany)
2019 Humboldt fellow, (Tuebingen, Germany)

Research Interests

Einstein's general relativity has been a celebrated achievement in Physics. It is now the standard theory for describing gravity in our universe. At the same time, various challenges to the theory exist, ranging from theoretical puzzles like singularities, to observational puzzles like dark energy and dark matter. Many resolutions have been proposed in theory for these issues. Some of them modify Einstein's theory of gravity, others propose additional features within Einstein's theory. Testing for these modifications is a field in its infancy; electromagnetic and gravitational radiation hold the promise in this regard. My interest lies on borderlands of the highly theoretical field of gravity and the highly observational field of astronomy.

With Prof. Bambi's group at Shanghai, I have developed RELXILL_NK (click through to access the model), a model for data analysis of X-rays to look for signatures of modified black holes. Click here for more.

With masters student Lorenzo Kuchler at Tuebingen, I have developed a new generic metric which serves as a theory-independent test of the nature of black holes.

With graduate student Alejandro Cardenas-Avendano at Montana State University, I am working on similar tests of black hole metrics using gravitational waves.

With Dr Victoria Grinberg in Tuebingen, I am investigating how systematic effects, for example interstellar gas, would affect the capabilities of X-ray instruments in testing gravity.

A crucial assumption of RELXILL_NK is the assumption that the accretion disk is infinitesimally thin and located on the equatorial plane. With graduate student Shafqat Riaz in Shanghai, I have studying the changes introduced by a thick disk.

Projects for the future

Here is a list of potential projects for students. If you are interested in working on any of them, feel free to drop an email or drop by my office.

TOPIC FOCUS (Red: Theory; Blue: Programming; Yellow: Data analysis)
Simultaneous GW X-ray study of black holes
Measuring the quadrupole moment of black holes with X-rays
Imaging non-kerr black holes
Analysis of systematic errors in RELXILL_NK
Analyzing multiple non-kerr parameters with X-rays
Analyzing Numerical non-kerr metrics with X-rays
Higher order GR effects on reflection spectrum

General information

Here is an assortment of general information on living/studying/etc. in Germany.

For a list of international Masters programs at Uni Tübingen, click here.

For a list of international Masters programs across Germany (website maintained by DAAD), click here.

Here you find a very active Facebook group popular among current/prospective students from India interested in studying in Germany.