Removal of nonphysical states

We have seen that there are some unphysical deformations.
One way to look at them is to consider the so-called beta deformation which is adding to the
action the wedge product of two global symmetry currents:

The corresponding unintegrated vertex is .
This is nonphysical when where is the structure constants of
the global symmetry group (super-Poincare). Notice that:

Therefore, we must postulate that: