Foundation of nonrelativistic string theory and its applications to holography
One of the most profound problems in modern theoretical physics concerns the formulation of quantum gravity. A predominating paradigm for addressing questions in quantum gravity is string theory. One important lesson from string theory is that different string theories must be unified in a nonperturbative theory called M-theory, to probe which corners of string theory with significant simplifications are valuable to consider. Notable examples of such corners are AdS/CFT duality and Matrix theory, with numerous applications to the information paradox in black hole physics, heavy-ion collisions in nuclear physics, superconductors in condensed matter, etc. The project focuses on a self-contained corner in string theory that treats space and time differently and has a nonrelativistic (NR) spectrum. This corner is called NR string theory. I will study the foundation of NR string theory and its relation to nonperturbative methods in string/M-theory. I will also explore applications to NR field theories, with impacts on condensed matter theories of ferromagnetism and 2D systems of electrons. During my PhD at UC Berkeley (US) and postdoc at Perimeter Institute (Canada), I  collaborated with some of the world experts in the field and sophisticated my expertise for this project. The host institution, Nordita, hosted by Stockholm University and KTH, provides an excellent environment for cutting-edge research on fundamental physics. The expertise among faculty members and postdocs, and the stimulating and extensive international visitor program at Nordita make it an ideal place to conduct this project and to sharpen my interdisciplinary skills in condensed matter and pure mathematics. In addition to my North American background, I also have long-term collaborations with research groups from prestigious EU institutions. The host, EU and I will all benefit from the international collaborations brought by the integrated background and worldwide connections of both the host and me.