Heating up the BIon

TL;DR

This paper introduces a new method to analyze D-brane probes in thermal backgrounds using the blackfold approach, revealing significant differences in phase structure compared to zero-temperature cases.

Contribution

It extends the DBI action framework to thermal backgrounds by developing a method for thermal equilibrium probes, applied specifically to the BIon solution.

Findings

Finite temperature alters the phase structure of BIon configurations.

At finite temperature, the system exhibits one or three phases, unlike the two phases at zero temperature.

The method enables studying D-brane probes in hot backgrounds in a consistent way.

Abstract

We propose a new method to consider D-brane probes in thermal backgrounds. The method builds on the recently developed blackfold approach to higher-dimensional black holes. While D-brane probes in zero-temperature backgrounds are well-described by the Dirac-Born-Infeld (DBI) action, this method addresses how to probe thermal backgrounds. A particularly important feature is that the probe is in thermal equilibrium with the background. We apply our new method to study the thermal generalization of the BIon solution of the DBI action. The BIon solution is a configuration in flat space of a D-brane and a parallel anti-D-brane connected by a wormhole with F-string charge. In our thermal generalization, we put this configuration in hot flat space. We find that the finite temperature system behaves qualitatively different than its zero-temperature counterpart. In particular, for a given separation between the D-brane and anti-D-brane, while at zero temperature there are two phases, at finite temperature there are either one or three phases available.