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

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.

Comments: 6 pages, 9 figures, v2:figure 2 replaced, one reference added, minor improvement, v3: one figure about density dependence of dispersion relations added, references added