Speaker
Description
A deformation of pure Yang-Mills theory by a phantom field similar to the
Faddeev-Popov ghost is considered. In this theory an Ersatz-supersymmetry
is identified which results in cancellation of quantum corrections up to two-
loop order. A quadruplet built from two complex fields in the adjoint – the
Faddeev-Popov ghost and the phantom Φ, all with the wrong statistics – balances four gauge fields a. At this level, the instanton measure and the β function is fully determined by quasiclassics. In a simple φ4 theory with a phantom added I identify a strictly conserved Ersatz-supercurrent. In the latter theory unitarity of amplitudes persists despite the presence of the phantom. In deformed Yang-Mills it is likely (although not proven) to persist too in all amplitudes with only gluon external legs. It remains to be seen whether this construction is just a device facilitating some loop calculations or broader applications can be found.