Anomaly Cancellations in the Type I D9-DFormula System and the USp(32) String Theory

We check some consistency conditions for the D9-D9 system in type I string theory. The gravitational anomaly and gauge anomaly for SO(n) × SO(m) gauge symmetry are shown to be cancelled when n − m = 32. In addition, we find that a string theory with USp(n) × USp(m) gauge symmetry also satisfies the ... View More