I am currently the Quantum Initiative Fellow at the Center for the Fundamental Laws of Nature, Harvard University. My primary academic advisor is Daniel Jafferis. Prior to my days at Harvard, I pursued my graduate studies under the guidance of Shiraz Minwalla.

Primary research interest

My current research interest includes understanding microscopic origin of various macroscopic gravitational objects such as black hole, black ring etc with primary focus on their thermodynamic and out-of-equilibrium entanglement properties. Find below a brief summary of my recent publications.

Thermal physics of small and large stringy black hole

Through the lens of holography, geometric properties of a gravitational theory in AdS get related to the entanglement of the conformal field theories on its boundary - this fact often goes by the name of ER=EPR. During my early days at Harvard, I established a new strong-weak duality on the worldsheet of strings in AdS₃ that is closely related to ER=EPR. Essentially the duality allows one to obtain a winding condensate description of the BTZ black hole (the large black hole in AdS₃). Utilizing such a description, Daniel Jafferis and I have been able to formulate an infinitesimally off-shell worldsheet technique (conceptually it is related to the Lewkowycz-Maldacena replica trick on the bulk) to calculate the thermal entropy of the blackhole from the first principle worldsheet calculation at weak strings coupling. Recently, such formalism is generalized for the application to Schwarzschild blackhole in large spacetime dimensions.

The winding condensate description of the strings in thermal AdS₃ mentioned above allowed the study of condensation of nearly marginal winding tachyon on the Euclidean time circle near Hagedorn temperature perturbatively directly from the worldsheet. Away from the Hagedorn temperature, the perturbation theory breaks down. At Hawking-Page temperature, I studied a specific double winding condensate CFT and conjectured it to be continuously connected to the perturbative solution mentioned above as we increase the temperature. This double winding condensate CFT is expected to describe a small stringy blackhole in AdS₃.

Black hole, black ring at zero temperature and F theoretic strings

Within the framework of superstring theory, the microstates of supersymmetric black hole and black ring in four dimensional flatspace is captured by the topological strings through Gopakumar-Vafa conjecture after using Gaiotto-Strominger-Yin correspondance. When the underlying Calabi-Yau lacks an elliptic fibration, proof of such a conjecture came only very recently through my work. I have pointed out that for various three-folds with one Kahler moduli the microcanonical entropy of the black hole is well approximated by an effective Cardy like formula. With Cumrun Vafa, I have investigated this phenomena further by looking at the conifold transition of the Calabi-Yau to a genus-one and elliptic three-fold where the microscopic counting can be formulated in terms of excitations of F theoretic strings. Very surprisingly we have found that the black hole is made out of light excitations of the string - which is in sharp contrast to the usual intuition of AdS/CFT.