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Entanglement Entropy after Double Excitation as an Interaction Measure
Yuya Kusuki1, Masamichi Miyaji2
1Center for Gravitational Physics, Yukawa Institute for Theoretical Physics (YITP), Kyoto University, Kitashirakawa Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
Physical Review Letters
|February 29, 2020
Summary
We investigated entanglement entropy in 2D conformal field theories (CFTs) after double local quenches. The universal growth is the sum of two quenches, minus a negative term attributed to gravity
Area of Science:
- Quantum Field Theory
- String Theory
- Condensed Matter Physics
Background:
- Entanglement entropy quantifies quantum correlations in a system.
- Local quenches perturb quantum field theories, leading to dynamic changes in entanglement.
- Holographic duality connects quantum field theories to gravitational theories in higher dimensions.
Purpose of the Study:
- To analyze entanglement entropy dynamics following a double local quench in 2D conformal field theories (CFTs).
- To explore the holographic interpretation of this phenomenon in anti-de Sitter space.
- To derive a universal formula for entanglement growth and understand its components.
Main Methods:
- Studying entanglement entropy in 2D CFTs subjected to double local excitations.
- Utilizing holographic duality, mapping CFT states to anti-de Sitter space with massive particles.
- Applying the fusion matrix approach for multipoint conformal blocks to evaluate six-point functions.
Main Results:
- The entanglement entropy growth after a double local quench is universal.
- This growth is equivalent to the sum of two independent local quenches, plus a negative contribution.
- The negative term is interpreted holographically as an attractive gravitational force.
Conclusions:
- The study provides a universal description of entanglement entropy dynamics after double local quenches in CFTs.
- Holography offers a compelling interpretation of the observed negative contribution to entanglement growth.
- The fusion matrix approach is a powerful tool for analyzing complex CFT correlation functions.
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