%0 Journal Article %T M(atrix) Theory on T9/Z2 Orbifold and Twisted Zero Brane %A N. Kim %A Soo-Jong Rey %J Physics %D 1997 %I arXiv %X M(atrix) theory compactified on an orbifold ${\bf T}_9/{\bf Z}_2$ is studied. Via zero-brane parton scattering we find that each of the $2^9 = 512$ orbifold fixed points carry $-1/32$ units of zero-brane charge. The anomalous flux is cancelled by introducing a twisted sector consisting of 32 zero-branes that are spacetime supersymmetry singlets. These twisted sector zero-branes are nothing but gravitational waves propagating along the M-theory direction. There is no D0-partons in the untwisted sector, a fact consistent with holographic principle. For low-energy excitations, the orbifold compactification is described by ten-dimensional supersymmetric Yang-Mills theory with gauge group $SO(32)$. %U http://arxiv.org/abs/hep-th/9710245v2