A. Bassetto et al., LIGHT-LIKE WILSON LOOPS AND GAUGE-INVARIANCE OF YANG-MILLS THEORY IN 1+1 DIMENSIONS, Physical review letters, 72(20), 1994, pp. 3141-3144
A lightlike Wilson loop is computed in perturbation theory up to O(g4)
for pure Yang-Mills theory in 1+1 dimensions, using Feynman and light
-cone gauges to check its gauge invariance, After dimensional regulari
zation in intermediate steps, a finite gauge invariant result is obtai
ned, which, however, does not exhibit Abelian exponentiation. Our resu
lt is at variance with the common belief that pure Yang-Mills theory i
s free in 1+1 dimensions, apart perhaps from topological effects.