A massless electroweak theory for leptons is formulated in a Weyl space, W-
4, yielding a Weyl invariant dynamics of a scalar field phi, chiral Dirac f
ermion fields psi(L) and psi(R), and the gauge fields K-mu, A(mu), Z(mu), W
-mu, and W-mu(dagger), allowing for conformal rescalings of the metric g(mu
nu) and all fields with nonvanishing Weyl weight together with the corresp
onding transformations of the Weyl vector fields, K-mu, representing the D(
1) or dilatation gauge fields. The local group structure of this Weyl elect
roweak (WEW) theory is given by G = SO(3, 1) circle times D(1) circle times
(G) over tilde-or its universal coverging group (G) over bar for the fermi
ons-with (G) over tilde denoting the electroweak gauge group SU(2)(W) x U(1
)(Y). In order to investigate the appearance of nonzero masses in the theor
y the Weyl symmetry is explicitly broken by a term in the Lagrangean constr
ucted with the curvature scalar R of the W-4 and a mass term for the scalar
field. Thereby also the Z(mu) and W-mu gauge fields as well as the charged
fermion field (electron) acquire a mass as in the standard electroweak the
ory. The symmetry breaking is governed by the relation D(mu)Phi(2) = 0, whe
re Phi is the modulus of the scalar field and D-mu denotes the Weyl-covaria
nt derivative. This true symmetry reduction, establishing a scale of length
in the theory by breaking the D(1) gauge symmetry, is compared to the so-c
alled spontaneous symmetry breaking in the standard electroweak theory, whi
ch is, actually, the choice of a particular (non-linear) gauge obtained by
adopting an origin, <(phi)over cap>, in the coset space representing phi, w
ith <(phi)over cap> being invariant under the electromagnetic, gauge group
U(1)(c.m.). Particular attention is devoted to the appearance of Einstein's
equations for the metric after the Weyl symmetry breaking, yielding a pseu
do-Riemannian space, V-4, from a W-4 and a scalar field with a constant mod
ulus <(phi)over cap>(0). The quantity <(phi)over cap>(2)(0) affects Einstei
n's gravitational constant in a manner comparable to the Brans-Dicke theory
. The consequences of the broken WEW theory are worked out and the determin
ation of the parameters of the theory is discussed.