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.
Electroweak theory and the Standard Model
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.
This article is in a list format that may be better presented using prose. (May 2017)
- 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. Through the AdS/QCD correspondence this model can be related to technicolor models and to UnHiggs models, in which the Higgs field is of unparticle nature.
- Unitary Weyl gauge. If one adds a suitable gravitational term to the standard model action with gravitational coupling, the theory becomes locally scale-invariant (i.e. Weyl-invariant) in the unitary gauge for the local SU(2). Weyl transformations act multiplicatively on the Higgs field, so one can fix the Weyl gauge by requiring that the Higgs scalar be a constant.
- Preon and models inspired by preons such as the Ribbon model of Standard Model particles by Sundance Bilson-Thompson, based in braid theory and compatible with loop quantum gravity and similar theories. This model not only explains the origin of mass, but also interprets electric charge as a topological quantity (twists carried on the individual ribbons), and colour charge as modes of twisting.
- In the theory of superfluid vacuum, masses of elementary particles arise from interaction with a physical vacuum, similarly to the gap generation mechanism in superfluids. The low-energy limit of this theory suggests an effective potential for the Higgs sector that is different from the Standard Model's, yet it yields the mass generation. Under certain conditions, this potential gives rise to an elementary particle with a role and characteristics similar to the Higgs boson.
- Steven Weinberg (1976), "Implications of dynamical symmetry breaking", Physical Review D, 13 (4): 974–996, Bibcode:1976PhRvD..13..974W, doi:10.1103/PhysRevD.13.974.
S. Weinberg (1979), "Implications of dynamical symmetry breaking: An addendum", Physical Review D, 19 (4): 1277–1280, Bibcode:1979PhRvD..19.1277W, doi:10.1103/PhysRevD.19.1277.
- Leonard Susskind (1979), "Dynamics of spontaneous symmetry breaking in the Weinberg-Salam theory", Physical Review D, 20 (10): 2619–2625, Bibcode:1979PhRvD..20.2619S, doi:10.1103/PhysRevD.20.2619, OSTI 1446928.
- Stancato, David; Terning, John (2009). "The Unhiggs". Journal of High Energy Physics. 0911 (11): 101. arXiv:0807.3961. Bibcode:2009JHEP...11..101S. doi:10.1088/1126-6708/2009/11/101. S2CID 17512330.
- Falkowski, Adam; Perez-Victoria, Manuel (2009). "Electroweak Precision Observables and the Unhiggs". Journal of High Energy Physics. 0912 (12): 061. arXiv:0901.3777. Bibcode:2009JHEP...12..061F. doi:10.1088/1126-6708/2009/12/061. S2CID 17570408.
- Dvali, Gia; Giudice, Gian F.; Gomez, Cesar; Kehagias, Alex (2011). "UV-Completion by Classicalization". Journal of High Energy Physics. 2011 (8): 108. arXiv:1010.1415. Bibcode:2011JHEP...08..108D. doi:10.1007/JHEP08(2011)108. S2CID 53315861.
- Goldfain, E. (2008). "Bifurcations and pattern formation in particle physics: An introductory study". EPL. 82 (1): 11001. Bibcode:2008EL.....8211001G. doi:10.1209/0295-5075/82/11001.
- Goldfain, E. (2010). "Non-equilibrium Dynamics as Source of Asymmetries in High Energy Physics" (PDF). Electronic Journal of Theoretical Physics. 7 (24): 219–234.
- Calmet, X. (2011), "Asymptotically safe weak interactions", Modern Physics Letters A, 26 (21): 1571–1576, arXiv:1012.5529, Bibcode:2011MPLA...26.1571C, CiteSeerX 10.1.1.757.7245, doi:10.1142/S0217732311035900, S2CID 118712775
- Calmet, X. (2011), "An Alternative view on the electroweak interactions", International Journal of Modern Physics A, 26 (17): 2855–2864, arXiv:1008.3780, Bibcode:2011IJMPA..26.2855C, CiteSeerX 10.1.1.740.5141, doi:10.1142/S0217751X11053699, S2CID 118422223
- Codello, A.; Percacci, R. (2009), "Fixed Points of Nonlinear Sigma Models in d>2", Physics Letters B, 672 (3): 280–283, arXiv:0810.0715, Bibcode:2009PhLB..672..280C, doi:10.1016/j.physletb.2009.01.032, S2CID 119223124
- Abbott, L. F.; Farhi, E. (1981), "Are the Weak Interactions Strong?", Physics Letters B, 101 (1–2): 69, Bibcode:1981PhLB..101...69A, CiteSeerX 10.1.1.362.4721, doi:10.1016/0370-2693(81)90492-5
- Csaki, C.; Grojean, C.; Pilo, L.; Terning, J. (2004), "Towards a realistic model of Higgsless electroweak symmetry breaking", Physical Review Letters, 92 (10): 101802, arXiv:hep-ph/0308038, Bibcode:2004PhRvL..92j1802C, doi:10.1103/PhysRevLett.92.101802, PMID 15089195, S2CID 6521798
- Csaki, C.; Grojean, C.; Murayama, H.; Pilo, L.; Terning, John (2004), "Gauge theories on an interval: Unitarity without a Higgs", Physical Review D, 69 (5): 055006, arXiv:hep-ph/0305237, Bibcode:2004PhRvD..69e5006C, doi:10.1103/PhysRevD.69.055006, S2CID 119094852
- Calmet, X.; Deshpande, N. G.; He, X. G.; Hsu, S. D. H. (2009), "Invisible Higgs boson, continuous mass fields and unHiggs mechanism", Physical Review D, 79 (5): 055021, arXiv:0810.2155, Bibcode:2009PhRvD..79e5021C, doi:10.1103/PhysRevD.79.055021, S2CID 14450925
- Pawlowski, M.; Raczka, R. (1994), "A Unified Conformal Model for Fundamental Interactions without Dynamical Higgs Field", Foundations of Physics, 24 (9): 1305–1327, arXiv:hep-th/9407137, Bibcode:1994FoPh...24.1305P, doi:10.1007/BF02148570, S2CID 17358627
- Bilson-Thompson, Sundance O.; Markopoulou, Fotini; Smolin, Lee (2007), "Quantum gravity and the standard model", Classical and Quantum Gravity, 24 (16): 3975–3993, arXiv:hep-th/0603022, Bibcode:2007CQGra..24.3975B, doi:10.1088/0264-9381/24/16/002, S2CID 37406474.
- V. Avdeenkov, Alexander; G. Zloshchastiev, Konstantin (2011). "Quantum Bose liquids with logarithmic nonlinearity: Self-sustainability and emergence of spatial extent". Journal of Physics B. 44 (19): 195303. arXiv:1108.0847. Bibcode:2011JPhB...44s5303A. doi:10.1088/0953-4075/44/19/195303. S2CID 119248001.
- G. Zloshchastiev, Konstantin (2011). "Spontaneous symmetry breaking and mass generation as built-in phenomena in logarithmic nonlinear quantum theory". Acta Physica Polonica B. 42 (2): 261–292. arXiv:0912.4139. Bibcode:2011AcPPB..42..261Z. doi:10.5506/APhysPolB.42.261. S2CID 118152708.
- Dzhunushaliev, Vladimir; G. Zloshchastiev, Konstantin (2013). "Singularity-free model of electric charge in physical vacuum: Non-zero spatial extent and mass generation". Cent. Eur. J. Phys. 11 (3): 325–335. arXiv:1204.6380. Bibcode:2013CEJPh..11..325D. doi:10.2478/s11534-012-0159-z. S2CID 91178852.