We propose a method to formulate four-dimensional N=1 super Yang-Mills theory
on the lattice without fine-tuning. We first show that four-dimensional Weyl
fermion in a real representation, which is equivalent to Majorana fermion, can
be formulated using the domain wall approach with an addition of a Majorana
mass term only for the unwanted mirror fermion. This formalism has manifest
gauge invariance. Fermion number conservation is violated only by the
additional Majorana mass term for the mirror fermion and the violation is
propagated to the physical fermion sector through anomalous currents. Due to
this feature, the formalism, when applied to the gluino in the present case,
ensures the restoration of supersymmetry in the continuum limit without
fine-tuning, unlike the proposal by Curci and Veneziano.Comment: 7 pages, TeX, no figure, final version accepted by Physics Letters
B.; explanation for exact chiral symmetry in L_5->\infty limit adde