Superon-graviton model and supersymmetric structure of spacetime and matter

A new Einstein-Hilbert type (SGM) action describing gravitational interaction of Nambu-Goldstone(N-G) fermion of nonlinear supersymmetry(NL SUSY) is obtained by performing the Einstein gravity analogue geometrical arguments in high symmetric four dimensional (SGM) spacetime. All elementary particles except graviton are regarded as the composite eigenstates of SO(10) super-Poincar\'e algebra(SPA) composed of the fundamental N-G fermion ``superons'' of NL SUSY. Some phenomenological implications of the composite picture of SGM, the linearlization of SGM and N = 2 Volkov-Akulov model are discussed.