%0 Journal Article %T Sixteen-fermion and related terms in M-theory on T**2 %A Michael B. Green %A Michael Gutperle %A Hwang-hyun Kwon %J Physics %D 1997 %I arXiv %R 10.1016/S0370-2693(97)01551-7 %X Certain one-loop processes in eleven-dimensional supergravity compactified on T**2 determine exact, non-perturbative, terms in the effective action of type II string theories compactified on a circle. One example is the modular invariant U(1)-violating interaction of sixteen complex spin-1/2 fermions of ten-dimensional type IIB theory. This term, together with the (curvature)**4 term, and many other terms of the same dimension are all explicitly related by supersymmetry. %U http://arxiv.org/abs/hep-th/9710151v3