Mass generation

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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 mass is strongly connected to gravitational interaction[why?], 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.

Background[edit]

Electroweak theory and the Standard Model[edit]

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.

Gravity-free models[edit]

In these theories, as in the Standard Model itself, the gravitational interaction either is not involved or does not play a crucial role.

Technicolor[edit]

Technicolor models break electroweak symmetry through gauge interactions, which were originally modeled on quantum chromodynamics.[1][2][further explanation needed]

Coleman-Weinberg mechanism[edit]

Coleman–Weinberg mechanism generates mass through spontaneous symmetry breaking through radiative corrections.[further explanation needed]

Other theories[edit]

  • Unparticle physics and the unhiggs[3][4] 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.[5]
  • Symmetry breaking driven by non-equilibrium dynamics of quantum fields above the electroweak scale.[6][7]
  • Models of composite W and Z vector bosons.[11]

Gravitational models[edit]

  • 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.[12][13] 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.[14]
  • 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.[15]
  • 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.[16] 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.[17] 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.[18][19] Under certain conditions, this potential gives rise to an elementary particle with a role and characteristics similar to the Higgs boson.

References[edit]

  1. ^ Steven Weinberg (1976), "Implications of dynamical symmetry breaking", Physical Review, D13 (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, D19 (4): 1277–1280, Bibcode:1979PhRvD..19.1277W, doi:10.1103/PhysRevD.19.1277. 
  2. ^ Leonard Susskind (1979), "Dynamics of spontaneous symmetry breaking in the Weinberg-Salam theory", Physical Review, D20 (10): 2619–2625, Bibcode:1979PhRvD..20.2619S, doi:10.1103/PhysRevD.20.2619. 
  3. ^ http://arxiv.org/PS_cache/arxiv/pdf/0807/0807.3961v2.pdf
  4. ^ http://arxiv.org/PS_cache/arxiv/pdf/0901/0901.3777v2.pdf
  5. ^ Dvali, Gia; Giudice, Gian F.; Gomez, Cesar; Kehagias, Alex (2011). "UV-Completion by Classicalization". arXiv:1010.1415Freely accessible. Bibcode:2011JHEP...08..108D. doi:10.1007/JHEP08(2011)108. 
  6. ^ "Bifurcations and pattern formation in particle physics: An introductory study". EPL (Europhysics Letters). 82: 11001. Bibcode:2008EL.....8211001G. doi:10.1209/0295-5075/82/11001. 
  7. ^ http://www.ejtp.com/articles/ejtpv7i24p219.pdf
  8. ^ Calmet, X. (2011), "Asymptotically safe weak interactions", Mod. Phys. Lett., A26: 1571–1576, arXiv:1012.5529Freely accessible, Bibcode:2011MPLA...26.1571C, doi:10.1142/S0217732311035900 
  9. ^ Calmet, X. (2011), "An Alternative view on the electroweak interactions", Int.J.Mod.Phys., A26: 2855–2864, arXiv:1008.3780Freely accessible, Bibcode:2011IJMPA..26.2855C, doi:10.1142/S0217751X11053699 
  10. ^ Codello, A.; Percacci, R. (2008), "Fixed Points of Nonlinear Sigma Models in d>2", Physics Letters B, 672 (3): 280–283, arXiv:0810.0715Freely accessible, Bibcode:2009PhLB..672..280C, doi:10.1016/j.physletb.2009.01.032 
  11. ^ Abbott, L. F.; Farhi, E. (1981), "Are the Weak Interactions Strong?", Physics Letters B, 101 (1–2): 69, Bibcode:1981PhLB..101...69A, doi:10.1016/0370-2693(81)90492-5 
  12. ^ 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/0308038Freely accessible, Bibcode:2004PhRvL..92j1802C, doi:10.1103/PhysRevLett.92.101802, PMID 15089195 
  13. ^ 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/0305237Freely accessible, Bibcode:2004PhRvD..69e5006C, doi:10.1103/PhysRevD.69.055006 
  14. ^ Calmet, X.; Deshpande, N. G.; He, X. G.; Hsu, S. D. H. (2008), "Invisible Higgs boson, continuous mass fields and unHiggs mechanism", Physical Review D, 79 (5): 055021, arXiv:0810.2155Freely accessible, Bibcode:2009PhRvD..79e5021C, doi:10.1103/PhysRevD.79.055021 
  15. ^ 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/9407137Freely accessible, Bibcode:1994FoPh...24.1305P, doi:10.1007/BF02148570 
  16. ^ Bilson-Thompson, Sundance O.; Markopoulou, Fotini; Smolin, Lee (2007), "Quantum gravity and the standard model", Class. Quantum Grav., 24 (16): 3975–3993, arXiv:hep-th/0603022Freely accessible, Bibcode:2007CQGra..24.3975B, doi:10.1088/0264-9381/24/16/002. 
  17. ^ A. V. Avdeenkov and K. G. Zloshchastiev, Quantum Bose liquids with logarithmic nonlinearity: Self-sustainability and emergence of spatial extent, J. Phys. B: At. Mol. Opt. Phys. 44 (2011) 195303. ArXiv:1108.0847.
  18. ^ K. G. Zloshchastiev, Spontaneous symmetry breaking and mass generation as built-in phenomena in logarithmic nonlinear quantum theory, Acta Phys. Polon. B 42 (2011) 261-292 ArXiv:0912.4139.
  19. ^ V. Dzhunushaliev and K.G. Zloshchastiev (2012). Singularity-free model of electric charge in physical vacuum: Non-zero spatial extent and mass generation. ArXiv:1204.6380.