2026/07/23 by Thomas Apostolidis, Matti Järvinen, Elias Kiritsis +3
#hep-th #cond-mat.stat-mech #cond-mat.str-el #gr-qc #nucl-th
Flavor-current correlators are studied in strongly-coupled dense (holographic) matter, at finite quark chemical potential μq and finite isospin asymmetry. The non-Abelian hydrodynamic description of the charged currents is derived in the presence of an isospin chemical potential μ3. The two-point correlators of charged currents are then computed holographically at finite quark and isospin chemical potentials. In the near-extremal hydrodynamic regime, ω, k, T, μ3 ≪ μ≡ √(μq2+μ32), relevant for cold strongly coupled matter, the IR properties of the correlators are studied. It is shown that in this regime, the correlators agree with the non-Abelian hydrodynamic predictions. Therefore, the traditional regime of validity of standard hydrodynamics extends beyond ω, k ≪ T ≪ μ to the so-called extended hydrodynamic regime T≪ ω, k ≪ μ. The holographic product formula is applied to the present non-Abelian system, and is used to propose an extended hydrodynamic approximation capturing both hydrodynamic-like poles and the leading effect of AdS2 poles, by resumming the low-ω logarithms. The results are verified through a detailed numerical analysis of the exact correlators and quasi-normal mode spectrum.