Holographic entanglement entropy in AdS3/WCFT

Entanglement is the most fundamental phenomenon in quantum mechanics, which denotes the unusual interactions of many-body systems in quantum regime. The entanglement entropy, defined by von Neumann entropy, thus, provides us a significant tool to understand the physics in quantum field theory, such as correlation, phase transition and quantum information. The dual picture of entanglement entropy in gravitational spacetime introduces the quantum behaviors into gravity, which suggests its prodigious role in quantum gravity apparently. In this paper, we consider AdS$_3$ with Comp$\grave{\mathrm{e}}$re-Song-Strominger (CSS) boundary conditions, under which the dual field theory is warped conformal field theory (WCFT), featuring a Virasoro-Kac-Moody algebra. We provide a holographic dual picture of the single interval entanglement entropy in WCFT in the bulk AdS$_3$. We explicitly show that bulk object captures the entanglement entropy in WCFT is a massive spinning particle's wordline that anchored on the boundary of the interval. Given the mass and spin of the particle as functions of quantum numbers of the twist operator in WCFT, the on-shell wordline action will match the entanglement entropy in WCFT.

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