A. Bassetto et al., WILSON LOOPS AND LIGHT-CONE GAUGE QUANTIZATION ON THE SPACE-TIME S(1)XR CYLINDER, Physical review. D. Particles and fields, 54(4), 1996, pp. 2845-2852
Yang-Mills theories on the S-1 x R cylinder are quantized at equal tim
e in the light-cone gauge A(-) = 0. Zero modes, related to the winding
around the cylinder, provide topological variables with a nontrivial
Hamiltonian. Positive and negative frequency components do contribute
to Green functions, in particular, to the free propagator, in a causal
way, leading to expressions different from the ones in the literature
. They are tested in the calculation of a Wilson loop with lightlike s
ides: in the Abelian case it can be exactly computed, obtaining the ex
pected exponentiation of the area; in the SU(N) case the area exponent
iation in terms of the Casimir constant of the fundamental representat
ion is obtained only if a ''contact form of the propagator is used. If
instead the causal propagator is adopted, only an O(g(4)) calculation
has been obtained entailing also the presence of the Casimir constant
of the adjoint representation.