Pratik Nandy

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Hello everyone! Welcome to my homepage.

Presently, I am an ExU (Extreme Universe collaboration) postdoctoral researcher at Yukawa Institute for Theoretical Physics (YITP), Kyoto University, Japan. My primary research is to explore the broad areas of quantum field theory, holography (quantum gravity), many-body systems, and quantum chaos using quantum information-theoretic tools. In the past, I also worked on the black hole information problem.

Currently, I am interested in understanding quantum chaos in holography and condensed matter systems. We probe such systems using a recently introduced measure known as Krylov complexity. The formalism relies on the construction of the Krylov basis, and a set of coefficients called Lanczos coefficients which measures the spreading of the operator through the Krylov chain. The ''universal operator growth hypothesis'' posits a universal behavior of these coefficients, stemming out of the Lanczos algorithm. By testing this hypothesis in systems showing saddle-dominated scrambling, we restrict and refine the hypothesis in a broader sense. We also formulate and extend this construction in open quantum systems, by generalizing the Lanczos algorithm to the Arnoldi iteration and bi-Lanczos algorithm. The output of our works proposes some universal way to characterize ''dissipative quantum chaos''. For more details, please refer to my list of publications.

I was also a visiting postdoc. at Princeton Center for Theoretical Science (PCTS), Princeton University, New Jersey, USA.

My research is supported by the JSPS Grant-in-Aid for Transformative Research Areas (A) "Extreme Universe" No. 21H05190.

Besides my research, I actively pursue traveling, hiking, and mountaineering activities. I also love to play guitar and piano in my leisure time.

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