  We investigate the infrared behaviour of the gluon propagator in Landau gauge
on a lattice with twisted boundary conditions. Analytic calculations using
Dyson-Schwinger equations, exact renormalization group and stochastic
quantization show that the gluon propagator in Landau gauge approaches zero for
small momentum. On the other hand lattice calculations and calculations on a
four-torus seem to give rise to a non-zero limit. One possible reason for this
difference is the existence of zero-momentum fluctuation modes which
potentially give a massive contribution to the gluon propagator. Our
simulations show that with twisted boundary conditions these zero-momentum
modes are suppressed and the gluon propagator becomes smaller than in a
periodic ensemble.
