Routing (electronic design automation)

Quantum mechanics

Theoretical physics

White hole

Schwarzschild radius

Spacetime

Mathematical physics

Entropy (arrow of time)

Event horizon

Computer science

Black hole thermodynamics

Computer network

Routing protocol

Physics

Quantum entanglement

Link-state routing protocol

Quantum

Black hole (networking)

Journal of High Energy Physics

We study the Page curve for asymptotically flat eternal Schwarzschild black holes in four and higher spacetime dimensions. Before the Page time, the entanglement entropy grows linearly in time. After the Page time, the entanglement entropy of a given region outside the black hole is largely modified by the emergence of an island, which extends to the outer vicinity of the event horizon. As a result, it remains a constant value which reproduces the Bekenstein-Hawking entropy, consistent with the finiteness of the von Neumann entropy for an eternal black hole.

Islands in Schwarzschild black holes