Mass generation

In theoretical physics, a mass generation mechanism is a theory that describes the origin of mass from the most fundamental laws of physics. Physicists have proposed a number of models that advocate different views of the origin of mass. The problem is complicated because the primary role of mass is to mediate gravitational interaction between bodies, and no theory of gravitational interaction reconciles with the currently popular Standard Model of particle physics. There are two types of mass generation models: gravity-free models and models that involve gravity. The Higgs mechanism is based on a symmetry-breaking scalar field potential, such as the quartic. The Standard Model uses this mechanism as part of the Glashow–Weinberg–Salam model to unify electromagnetic and weak interactions. This model was one of several that predicted the existence of the scalar Higgs boson. In these theories, as in the Standard Model itself, the gravitational interaction either is not involved or does not play a crucial role. Technicolor models break electroweak symmetry through gauge interactions, which were originally modeled on quantum chromodynamics. Coleman–Weinberg mechanism generates mass through spontaneous symmetry breaking. Unparticle physics and the unhiggs models posit that the Higgs sector and Higgs boson are scaling invariant, also known as unparticle physics. UV-Completion by Classicalization, in which the unitarization of the WW scattering happens by creation of classical configurations. Symmetry breaking driven by non-equilibrium dynamics of quantum fields above the electroweak scale. Asymptotically safe weak interactions based on some nonlinear sigma models. Models of composite W and Z vector bosons. Top quark condensate. Extra-dimensional Higgsless models use the fifth component of the gauge fields in place of the Higgs fields. It is possible to produce electroweak symmetry breaking by imposing certain boundary conditions on the extra dimensional fields, increasing the unitarity breakdown scale up to the energy scale of the extra dimension.