CORDIS - Forschungsergebnisse der EU
CORDIS

Strongly Coupled Gauge Theories at Finite Density

Final Report Summary - FD HOLOG (Strongly Coupled Gauge Theories at Finite Density)

This project addressed two problems in strongly coupled theories at finite density. The first was implemented in the context of non-relativistic correspondence of the ads/CFT type at finite density. The focus is on the calculation of transport coefficients, like conductivity. Such observables are very important xperimentally in many systems as the capture the response of the medium to small external fields.
A new classification of gravitational systems that possess a non-relativistic Schrodinger symmetry was formulated by considering standard metrics written in the light-cone frame. This method allows the fast computation of renormalized correlators and transport coefficients, that are very important in order to characterize the behavior of such systems for applications, especially in condensed matter systems. This was published in arXiv:1008.3286.
Its first application, to the physics of strange metals was also done and published in arXiv:1012.3464.
The next application involved dimensionally reduced large-N theories with the aim of understanding more complex behavior at strong coupling.
Dimensionally reduced effective actions for QCD and theories alike have been analyzed. In particular, the reduction of a spatial direction with periodic boundary condition on the fermions was examined. The aim of this project was to construct dimensionally reduced effective actions of QCD-like theories with one compactified direction. When the compact direction is the time axis, this is the well-known high-temperature 3d effective action. The interest here is in compactifying the theories on a spatial direction. The difference is that we can impose periodic boundary condition on the fermions and the resulting effective action contains fermions, unlike the case with high temperature. The motivation comes from the studies of adjoint QCD which contains fermions in adjoint representation.