Thermal Fluctuation and Meson Melting: Holographic Approach

TL;DR

This paper uses holographic duality to analyze how thermal fluctuations cause meson dissociation in strongly coupled gauge theories, revealing phase transitions and instability mechanisms.

Contribution

It demonstrates how thermal fluctuations induce instability and phase transitions in mesons via holography, linking imaginary parts of the brane action to meson thermal widths.

Findings

Thermal fluctuations lead to an imaginary component in the brane action, signaling instability.

The thermal width of mesons increases as quark mass decreases.

Thermal width also increases with temperature at fixed quark mass.

Abstract

We use gauge/gravity duality to investigate the effect of thermal fluctuations on the dissociation of the quarkonium meson in strongly coupled $(3+1)$-dimensional gauge theories. This is done by studying the instability and probable first order phase transition of a probe D7-brane in the dual gravity theory. We explicitly show that for the Minkowski embeddings with their tips close to the horizon in the background, the long wavelength thermal fluctuations lead to an imaginary term in their action signaling an instability in the system. Due to this instability, a phase transition is expected. On the gauge theory side, it indicates that the quarkonium mesons are not stable and dissociate in the plasma. Identifying the imaginary part of the probe barne action with the thermal width of the mesons, we observe that the thermal width increases as one decreases the mass of the quarks. Also keeping the mass fixed, thermal width increases by temperature as expected.