Holographic approach of the spinodal instability to criticality

Understand

A smoking gun signature for a first-order phase transition with negative speed of sound squared $c_s^2$ is the occurrence of a spinodal instability.

• In the gauge/gravity duality it corresponds to a Gregory-Laflamme type instability, which can be numerically simulated as the evolution of unstable planar black branes.
• Making use of holography its dynamics is studied far from and near a critical point with the following results.
• Near a critical point the interface between cold and hot stable phases, given by its width and surface tension, is found to feature a wider phase separation and a smaller surface tension.