  We extend the BFSS matrix theory by means of Lie 3-algebra. The extended
model possesses the same supersymmetry as the original BFSS matrix theory, and
thus as the infinite momentum frame limit of M-theory. We study dynamics of the
model by choosing the minimal Lie 3-algebra that includes u(N) algebra. We can
solve a constraint in the minimal model and obtain two phases. In one phase,
the model reduces to the original matrix model. In another phase, it reduces to
a simple supersymmetric model.
