Electroweak Symmetry Breaking

Looking at the field Σ:
Σ(x) = exp
(− i )
v w(x)
with w(x) = w a (x) τ a , a = 1, 2, 3,
So far, it was a mathematical construct, and the scalar fields w a
parameterizing Σ were unphysical. In fact, their scattering
amplitudes are related to the scattering amplitudes of
longitudinally polarized massive vector bosons.
Alternatively, there may be more content associated to Σ.
Simple possibility: relax the constraint on Σ:
with a real constant c.
Σ † Σ = c × 1 (1)