Sum rules, plasma frequencies and Hall phenomenology in holographic plasmas

TL;DR

This paper investigates the optical and Hall conductivities in holographic plasmas with Dp/Dq-branes, revealing how massive matter and defects influence plasma frequency and transport properties through sum-rule analysis.

Contribution

It provides a detailed holographic analysis of how massive fundamental matter and defects affect plasma frequencies and transport coefficients, with a focus on sum-rule implementation.

Findings

Massive matter reduces plasma frequency in holographic plasmas.

Defects alter the impact of matter on plasma frequency.

Proper regularization of Green's functions ensures physical dispersion relations.

Abstract

We study the AC optical and hall conductivities of Dp/Dq-branes intersections in the probe approximation and use sum-rules to study various associated transport coefficients. We determine that the presence of massive fundamental matter, as compared to massless fundamental matter described holographically by a theory with no dimensional defects, reduces the plasma frequency. We further show that this is not the case when the brane intersections include defects. We discuss in detail how to implement correctly the regularization of retarded Green's functions so that the dispersion relations are satisfied and the low energy behaviour of the system is physically realistic.