Exploring String Theory with and without Supersymmetry

This award funds the research activities of Professor Savdeep Sethi at the University of Chicago. The microscopic structure of space and time are one of the enduring mysteries of nature. Did space and time emerge in some kind of Big Bang? Will the universe end in a Big Crunch? What is the nature of dark energy? In order to answer such basic questions about the physics of our universe, we need a quantum theory of gravity. String theory remains our leading candidate for such a theory. In his research, Professor Sethi aims to explore the physics of string theories both with and without a remarkable structure called supersymmetry. This research program has concomitant broader impacts in four areas. The first comes from providing research opportunities for undergraduates, including continued participation in the Summer REU Opportunities for Minorities and Women program at the University of Chicago, and through direct research opportunities. The second is promoting equity by organizing conferences like the Conference for Undergraduate Women in Physics. The third is through public outreach programs like the Life Long Learning program. The final aspect involves improving interdisciplinary ties with both cosmologists and mathematicians through lectures at schools and workshops, through direct collaboration and by organizing workshops. The research goals center on several broad topics. The first is exploring the three known non-supersymmetric string theories in ten dimensions. The specific goal is investigating the space-time potential energy and understanding the nature of its critical points. This potential is an ingredient in recently constructed models that provide laboratories for exploring holography without supersymmetry. The second set of questions involve supersymmetry in differing ways: the first is to explore more deeply quantum field theories deformed by irrelevant operators. The second is to develop a symbolic computation package that can generate supersymmetric Lagrangians with higher derivative couplings. The third is to study the moduli space of compactified field theory with the aim of computing partition functions via localization. The fourth direction is to finally unravel the complete set of constraints imposed by maximal supersymmetry in field theory and supergravity. The final topic is to connect the program in mathematics to classify Fano four-folds to M-theory AdS flux solutions in three dimensions. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.