Routing (electronic design automation)

Quantum mechanics

Theoretical physics

Entropy (arrow of time)

Computer science

Black hole thermodynamics

Computer network

Thermodynamics

Routing protocol

Physics

Instability

Mathematics

Link-state routing protocol

Mathematical analysis

Black hole (networking)

Isoperimetric inequality

Modern Physics Letters A

The charged black hole of Banados, Teitelbiom and Zanelli is studied in extended gravitational thermodynamics where there is a dynamical pressure and volume. It is a simple example of a super-entropic black hole, violating the reverse isoperimetric inequality. It is proven that this property implies that its specific heat at constant volume is negative, signalling a new kind of fundamental instability for black holes. It is conjectured that this instability is present for other super-entropic black holes, and this is demonstrated numerically for a large family of known solutions.

Instability of super-entropic black holes in extended thermodynamics