Light-cone vacuum in (1+1)-dimensional super-Yang-Mills theory - art. no. 115006

The discrete light-cone quantization (DLCQ) of a supersymmetric SU(N) gauge theory in 1+1 dimensions is discussed, with particular emphasis given to t he inclusion of all dynamical zero modes. Interestingly, the notorious "zer o-mode problem" is now tractable because of special supersymmetric cancella tions. In particular, we show that anomalous, zero-mode contributions to th e currents are absent, in contrast with what is observed in the non-supersy mmetric case. We find that the supersymmetric partner of the gauge zero mod e is the diagonal component of the fermion zero mode. An analysis of the va cuum structure is provided and it is shown that the inclusion of zero modes is crucial for probing the phase properties of the vacua. In particular, w e find that the ground state energy is zero and N-fold degenerate, and thus consistent with unbroken supersymmetry. We also show that the inclusion of zero modes for the light-cone supercharges leaves the supersymmetry algebr a unchanged. Finally, we remark that the dependence of the light-cone Fock vacuum in terms of the gauge zero is unchanged in the presence of matter fi elds. [S0556-2821(99)04323-4].