Seminar detail: Multi-trace measure in AdS3/CFT2

Date&Time	Mon May 13 2024 (13:00 - 14:00)
Speaker	Jonathan Harper
Affiliation	YITP, Kyoto U
Title	Multi-trace measure in AdS3/CFT2
Abstract	The multi-trace generalizes the trace of many copies of the reduced density matrix of a quantum state by considering tensor contractions of the various parties with respect to a general finite symmetry group. Analogous to the entanglement entropy, the multi-trace can then be used to define "multi-trace measures", potential measures of multi-party entanglement. I will highlight how this structure allows for an equivalent geometric description in terms of q-point functions of twist operators for 2d CFTs and provide several examples. For a static time slice of AdS3 I will describe a particular class of minimal surfaces which form trivalent networks of geodesics and through geometric arguments provide evidence that these surfaces describe a measure of multipartite entanglement. By relating these surfaces to Ryu-Takayanagi surfaces I will show that this multipartite contribution is related to the angles of intersection of the bulk geodesics. A proposed boundary dual, the multi-entropy, is an example of such a multi-trace measure. Throughout the talk I will emphasize several related mathematical frameworks including: Riemann surfaces, handlebody orbifolds, and semi-classical Liouville theory.
Remarks
Slide/Video	slide1