Generation of vector boson masses in Electroweak Model without dynamical symmetry breaking

The vector boson masses are generated by transformation of the free (without any potential term) Lagrangian of the Electroweak Model from Cartesian coordinates to a coordinates on the sphere S3, which is defined by the gauge invariant quadratic form φ†φ = ρ2 in the matter field space Φ2. This transformation corresponds to transition from linear representation of the gauge group in the space Φ2 to its nonlinear representation in the space of functions on S3. Such modified Electroweak Model keep all experimentally verified fields of the standard Electroweak Model and does not include massive scalar field (Higgs boson), if the sphere radius does not depend on the space-time coordinates ρ = R = const. The concept of generation masses for vector bosons in Electroweak Model by transformation to radial coordinates is further developed in context of nonlinearly realized gauge groups, as well as in context of nonlinear sigma models. The limiting case of the modified Electroweak Model which corresponds to the contracted gauge group is discussed.