Self-energy of Strongly Interacting Fermions in Medium: a Holographic Approach

TL;DR

This paper investigates the self-energy of strongly interacting fermions in a medium using holographic duality, revealing differences from traditional methods and identifying conditions for plasmino modes.

Contribution

It introduces a holographic approach to analyze fermion self-energy, thermal mass, and plasmino behavior in strongly coupled media, contrasting with existing thermal field theory results.

Findings

No thermal mass or plasmino at zero density.

Plasmino modes are absent in deconfined phase.

Plasmino modes exist only within a density window in the confined phase.

Abstract

We consider the self-energy of strongly interacting fermions in the medium using gauge/gravity duality of $D4/D8$ system. We study the mass generation of the thermal and/or dense medium and the collective excitation called plasmino, by considering the spectral function of fermion and its dispersion relation. Our results are very different from those of the hard thermal loop method: for zero density, there is no thermal mass or plasmino in any phase. Plasmino in deconfined phase is not allowed in $D4/D8$ set up. In the confined phase, there is plasmino modes only for a window of density.