Separating the scales of confinement and chiral-symmetry breaking in lattice QCD with fundamental quarks

TL;DR

This study uses lattice QCD simulations with additional 4-fermion interactions to demonstrate that confinement and chiral-symmetry breaking scales can be independently varied, supporting holographic duality predictions.

Contribution

It provides the first lattice evidence that extra 4-fermion terms can separate the confinement and chiral-symmetry breaking scales in QCD.

Findings

Deconfinement occurs at lower temperature than chiral restoration with strong 4-fermion coupling.

Separation of transition scales depends on the 4-fermion coupling strength.

Results support holographic duality predictions for independent scale variation.

Abstract

Suggested holographic duals of QCD, based on AdS/CFT duality, predict that one should be able to vary the scales of colour confinement and chiral-symmetry breaking independently. Furthermore they suggest that such independent variation of scales can be achieved by the inclusion of extra 4-fermion interactions in QCD. We simulate lattice QCD with such extra 4-fermion terms at finite temperatures and show that for strong enough 4-fermion couplings the deconfinement transition occurs at a lower temperature than the chiral-symmetry restoration transition. Moreover the separation of these transitions depends on the size of the 4-fermion coupling, confirming the predictions from the proposed holographic dual of QCD.