BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Everything Everywhere All at Once: Holographic Entropy Inequalitie
 s\, the Topology of Error Correction\, Black Holes\, Cubohemioctahedron\, 
 and (maybe) the Toric Code - Bartek Czech (Tsinghua University)
DTSTART:20231128T150000Z
DTEND:20231128T160000Z
UID:TALK203692@talks.cam.ac.uk
DESCRIPTION:An important class of quantum states are those whose entanglem
 ent entropies can be computed by minimal cuts through some bulk structure-
 --a holographic spacetime or a random tensor network. Such states obey lin
 ear constraints on their entanglement entropies\, which are known as holog
 raphic entropy inequalities. I present two new infinite families of hologr
 aphic entropy inequalities. The entropies featured in these inequalities a
 re best visualized on graphs whose incidence relations reflect subsystem i
 nclusion. These graphs turn out to be tessellations of the torus and the r
 eal projective plane. The non-contractible cycles on these manifolds play 
 an indispensable role in proving the inequalities\, which shows that they 
 hold for essentially topological reasons. Physically\, the inequalities re
 present constraints on holographic error correcting codes and\, in some ca
 ses\, the entropy of two-sided black holes. If time allows it\, I will ske
 tch bonus applications\, which involve a non-planar polytope called "cuboh
 emioctahedron" and (more speculatively) the toric code.Co-authors: Sirui S
 huai\, Yixu Wang\, Daiming Zhang
LOCATION:Seminar Room 1\, Newton Institute
END:VEVENT
END:VCALENDAR