Finite temperature quark confinement via chromomagnetic fields

A natural mechanism for finite temperature quark confinement arises via the coupling of the adjoint Polyakov loop to the chromomagnetic field. Lattice simulations and analytical results both support this hypothesis. Finite temperature SU(3) lattice simulations show that a large external coupling to the chromomagnetic field restores confinement at temperatures above the normal deconfining temperature. A one-loop calculation of the effective potential for SU(2) gluons in a background field shows that a constant chromomagnetic field can drive the Polyakov loop to confining behavior, and the Polyakov loop can in turn remove the well-known tachyonic mode associated with gluons in an external chromomagnetic field. For abelian background fields, tachyonic modes are necessary for confinement at one loop. (orig.)