In 1998, he won the fellowship of the Royal Society on being nominated by the theoretical physicist Stephen Hawking. His contributions include the entropy function formalism for extremal black holes and its applications to attractors. His recent important works include the attractor mechanism and the precision counting of microstates of black holes, and new developments in string perturbation theory. He joined the National Institute of Science Education and Research (NISER) India as an honorary professor in the School of Physical Sciences. In the year 2020, he joined Indian Institute of Science Education and Research, Bhopal (IISER Bhopal), Bhopal, Madhya Pradesh, India as a Visiting / Adjunct Professor in the department of Physics. He is currently serving as a distinguished professor at the International Centre for Theoretical Sciences (ICTS), Bangalore where he is working on string theory. His specific research interests include S-duality, tachyon condensation, black hole entropy and superstring perturbation theory.