There is a further possibility that the physical vacuum (ground-state) does not respect the symmetries implied by the "unbroken" electroweak Lagrangian from which one arrives at the field equations (see the article Electroweak interaction for more details). The electroweak theory of Weinberg and Salam was shown to be renormalizable (finite) and hence consistent by Gerardus 't Hooft and Martinus Veltman. The Glashow–Weinberg–Salam theory (GWS theory), in certain applications, gives an accuracy on a par with quantum electrodynamics.