#### Alladi Ramakrishnan Hall

#### Generalized entanglement entropy and holography

#### Nana Cabo-Bizet

##### University of the Witwatersrand, South Africa

*In this work, we first introduce a generalized von Neumann entropy that *

depends only on the density matrix. This is based on a previous proposal

by one of us modifying the Shannon entropy by considering

non-equilibrium systems on stationary states, and an entropy functional

depending only on the probability. We propose a generalization of the

replica trick and find that the resulting modified von Neumann entropy

is precisely the previous mentioned entropy that was obtained by other

assumptions. Then, we address the question whether alternative

entanglement entropies can play a role in the gauge/gravity duality. Our

focus are 2dCFT and their gravity duals. Our results show corrections to

the von Neumann entropy S0 that are larger than the usual UV ones and

also than the corrections to the length dependent AdS3 entropy which

result comparable to the UV ones. The correction terms due to the new

entropy would modifythe Ryu-Takayanagi identification between the CFT

and the gravitational AdS3 entropies.

Done