24.02.2021 (Wednesday)

Quantum Field Theory and Beyond

Polygon Seminar Nathan Seiberg (IAS)

15:00 IC
room online

The first talk will be general, i.e., at a colloquium level. The second talk will be more technical, i.e., at a seminar level. Yet, each of the two talks will be self-contained. For this reason, there will be some overlap between them. Talk 1: Quantum Field Theory and Beyond We will review the status of Quantum Field Theory (QFT) and will present it as “the language of physics.” Using examples from string theory and condensed matter physics, we will motivate the fact that the standard framework of QFT should be extended. As specific examples, we will review the phenomena of fractons, which do not seem to fit the standard framework of continuum QFT. We will then present recent attempts to incorporate fractons in a slightly generalized version of quantum field theory. Talk 2: Fractons: going beyond standard QFT Starting with a lattice system at short distances, its long-distance behavior is captured by a continuum Quantum Field Theory (QFT). This description is universal, i.e., it is independent of most of the details of the microscopic system. Surprisingly, certain recently discovered lattice systems, and in particular models of fractons, seem to violate this general dogma. Motivated by this apparent contradiction, we will present exotic continuum QFTs that describe these systems.