Holographic Local Quenches and Entanglement Density

TL;DR

This paper models local quantum quenches holographically using a falling particle in AdS space, analyzing entanglement evolution and introducing entanglement density to relate quantum information to energy.

Contribution

It introduces a holographic model for local quenches and proposes entanglement density as a new tool to analyze quantum entanglement structures.

Findings

Logarithmic time-evolution of entanglement entropy in local quenches

Entanglement density relates to energy density in small limits

Simple relation between quantum information and energy in AdS/CFT

Abstract

We propose a free falling particle in an AdS space as a holographic model of local quench. Local quenches are triggered by local excitations in a given quantum system. We calculate the time-evolution of holographic entanglement entropy. We confirm a logarithmic time-evolution, which is known to be typical in two dimensional local quenches. To study the structure of quantum entanglement in general quantum systems, we introduce a new quantity which we call entanglement density and apply this analysis to quantum quenches. We show that this quantity is directly related to the energy density in a small size limit. Moreover, we find a simple relationship between the amount of quantum information possessed by a massive object and its total energy based on the AdS/CFT.