Analytic and numerical study of the free energy in gauge theory

作者：Maas Axel^*; Zwanziger Daniel

来源：Physical Review D - Particles, Fields, Gravitation and Cosmology, 2014, 89(3): 034011.

DOI：10.1103/PhysRevD.89.034011

We derive some exact bounds on the free energy W(J) in an SU (N) gauge theory, where J(mu)(b) is a source for the gluon field A(mu)(b) in the minimal Landau gauge, and W(J) is the generating functional of connected correlators, exp W(J) = %26lt; exp(J, A)%26gt;. We also provide asymptotic expressions for the free energy W(J) at large J and for the quantum effective action Gamma(A) at large A. We specialize to a source J(x) = h cos (k . x) of definite momentum k and source strength h, and study the gluon propagator D(k, h) in the presence of this source. Among other relations, we prove f(0)(alpha) dhD(k,h) %26lt;= root 2k which implies lim(k -%26gt; 0)D(k, h) = 0, for all positive h %26gt; 0. Thus the system does not respond to a static color probe, no matter how strong. Recent lattice data in minimal Landau gauge in d = 3 and 4 dimensions at h = 0 indicate that the gluon propagator in the minimum Landau gauge is finite, lim(k -%26gt; 0)D (k,0) %26gt; 0. Thus these lattice data imply a jump in the value of D(k, h) at h = 0 and k = 0, and the value of D(k, h) at this point depends on the order of limits. We also present numerical evaluations of the free energy W(k, h) and the gluon propagator D(k, h) for the case of SU(2) Yang-Mills theory in various dimensions which support all of these findings.

• 出版日期2014-2-6