Seminars & Colloquia Calendar
The SYK model: a window into black holes and non-Fermi liquids
Subir Sachdev - Harvard University
Date & time: Wednesday, 18 August 2021 at 10:45AM - 11:45AM
Abstract: The Sachdev-Ye-Kitaev model is perhaps the only solvable quantum many-body system without quasiparticle excitations. I will introduce some of its basic properties, and describe its low energy theory, expressed in terms of a path integral over time reparameterizations. I will then introduce the Gibbons-Hawking quantum theory of charged black holes in Einstein gravity, and show that it has the same low temperature theory as the SYK model: this yields a universal correction to the Bekenstein-Hawking black hole entropy. The resulting picture of the low energy states of a black hole differs from that of supersymmetric black holes solved via string theory. Finally I will discuss a quantum generalization of the Sherrington-Kirkpatrick spin glass model, with S=1/2 spins, SU(2) spin symmetry, and mobile charge carriers: this displays non-Fermi liquid physics connected to the SYK model.