# Holographic Entropy Cone from Marginal Independence

- Institution: CERN
- Department: Conferences & Workshops
- Speaker: Veronika Hubeny
- Year: 2021
- Language: English
- Source: [CERN](https://videos.cern.ch/record/3011493)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Teens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

This talk will explain recent puzzling revelations in the ongoing efforts to obtain a useful characterization of entanglement structure of geometric states in a holographic CFT, via the so-called holographic entropy cone (HEC). The relations between subsystem entanglement entropies which delimit this cone are known explicitly for only a rather coarse subdivision of the system (specified by N spatial regions, for up to N = 5). We argue that, subject to a certain graph theoretic conjecture, the task of finding the HEC for arbitrary N can be recast in terms of a much simpler combinatorial one which effectively reduces to the connectivity of entanglement wedges. More specifically, the N-party HEC can be reconstructed by solving the holographic marginal independence problem (HMIP) for a finer subdivision N′ ≥ N, which technically amounts to identifying which extreme rays of this subadditivity cone are realizable holographically. Curiously, despite the fact that subadditivity is a universal property which states that total correlation cannot be negative, the non-trivial facets of the HEC constructed therefrom nevertheless cannot be recast as correlation measures..

0:00:00 Slide 1

0:04:58 Slide 2

0:09:56 Slide 3

0:14:53 Slide 4

0:19:51 Slide 5

0:24:48 Slide 6

0:29:46 Slide 7

0:34:43 Slide 8

0:39:41 Slide 9

0:44:38 Slide 10

0:49:36 Slide 11

## Lectures

1. [Holographic Entropy Cone from Marginal Independence](https://invisiblenetwork.ai/learn/cern/3011493/074ae29de5a2), 50 min (CERN's player)