Straightening Out the Frobenius-Schur Indicator

Steven H. Simon, Joost K. Slingerland

The Frobenius-Schur indicator is a parameter ${\kappa }_a=\pm 1$ assigned to each self-dual particle $a$ in a TQFT. If ${\kappa }_a$ is negative then straightening out a timelike zig-zag in the wo…