Research in Field Theory and String Theory

This award funds the research activities of Sumit R. Das at the University of Kentucky. A major goal of current theoretical physics is to reconcile the laws of Quantum Mechanics which describes microscopic phenomena and the laws of General Relativity which describes gravitational forces in the macroscopic world. This project aims to address several issues which arise in this quest. A major theme of the proposed research is quantum entanglement, a key property of quantum mechanics which is playing a crucial role in modern attempts to provide a description of gravity in a way which is consistent with quantum laws. Quantum entanglement plays an important role in our current understanding of quantum phenomena and quantum materials necessary to build quantum computers. Consequently, a deeper understanding of entanglement will serve the national interest by advancing fundamental science. This is the main intellectual merit of this project. The PI will involve graduate students and postdoctoral scholars in this research, thus providing them with valuable training necessary to develop into independent scientists and educators. In addition, the results will be used to enhance classroom education both at the graduate and undergraduate levels. The PI also plans to give public talks about the subject in various forums and lectures at “Osher Lifelong Learning Institute” which offers courses and enrichment programs to members of the community. More technically, Das will study aspects of the Holographic Correspondence which relates gravitational theories to non-gravitational theories in lower number of space-time dimensions. The additional dimensions are emergent and entanglement properties of the non-gravitational theory play a vital role in this emergence. The proposed research has four goals. The first is to continue investigation of notions of entanglement of internal degrees of freedom developed by the PI recently and explore their role in the emergence of internal spaces. These notions also provide useful tools to understand quantum properties of many body systems, exploring this aspect is a second goal. The third goal is to apply ideas from tensor networks to throw light on the nature of time evolution in expanding cosmology: there are reasons to believe that this is different from time evolution of usual systems. The aim will be to explore implications for a possible holographic description. The fourth goal is to further develop a recent method developed by the PI to study non-equilibrium processes in certain quantum field theories in arbitrary number of dimensions exactly and understand the time evolution of quantum entanglement in these systems.