Spectral functions in V-QCD with matter: masses, susceptibilities, diffusion and conductivity

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Regular Article - Theoretical Physics


We consider a holographic model of QCD in the Veneziano limit of a large number of colors N c and flavors N f but fixed x = N f /N c (V-QCD). The model exhibits a first order deconfined but chirally broken transition, followed by a second order chirally restored transition in the μT plane for a range of plausible holographic parameters. We study the quasi-normal mode spectrum, and derive the pertinent vector and axial spectral functions across the transition regions. The pole masses, susceptibilities, diffusion constants and electric conductivity are also discussed. In particular, the pole masses are found to survive the deconfining transition, to quickly dissolve in the the chirally restored phase by developing substantial widths. The flavor electric conductivities arise sharply in the transition region. The flavor susceptibility is shown to be consistent with the one derived from bulk thermodynamics.


Quark-Gluon Plasma Gauge-gravity correspondence Holography and quarkgluon plasmas Phase Diagram of QCD 


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© The Author(s) 2015

Authors and Affiliations

  1. 1.Department of Physics and AstronomyStony Brook UniversityStony BrookUnited States

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