In theoretical physics, explicit symmetry breaking is the breaking of a symmetry of a theory by terms in its defining equations of motion (most typically, to the Lagrangian or the Hamiltonian) that do not respect the symmetry. Usually this term is used in situations where these symmetry-breaking terms are small, so that the symmetry is approximately respected by the theory. An example is the spectral line splitting in the Zeeman effect, due to a magnetic interaction perturbation in the Hamiltonian of the atoms involved.
Explicit symmetry breaking differs from spontaneous symmetry breaking. In the latter, the defining equations respect the symmetry but the ground state (vacuum) of the theory breaks it.[1]
Explicit symmetry breaking is also associated with electromagnetic radiation. A system of accelerated charges results in electromagnetic radiation when the geometric symmetry of the electric field in free space is explicitly broken by the associated electrodynamic structure under time varying excitation of the given system. This is quite evident in an antenna where the electric lines of field curl around or have rotational geometry around the radiating terminals in contrast to linear geometric orientation within a pair of transmission lines which does not radiate even under time varying excitation.[2]
^Castellani, E. (2003) "On the meaning of Symmetry Breaking" in Brading, K. and Castellani, E. (eds) Symmetries in Physics: New Reflections, Cambridge: Cambridge University Press
^Sinha & Amaratunga (2016) "Explicit Symmetry Breaking in Electrodynamic Systems and Electromagnetic Radiation" Morgan Claypool, Institute of Physics, UK
and 24 Related for: Explicit symmetry breaking information
In theoretical physics, explicitsymmetrybreaking is the breaking of a symmetry of a theory by terms in its defining equations of motion (most typically...
In physics, symmetrybreaking is a phenomenon where a disordered but symmetric state collapses into an ordered, but less symmetric state. This collapse...
the underlying physical laws remain symmetrical. Conversely, in explicitsymmetrybreaking, if two outcomes are considered, the probability distributions...
In particle physics, chiral symmetrybreaking generally refers to the dynamical spontaneous breaking of a chiral symmetry associated with massless fermions...
effect, soft SUSY breaking adds explicitsymmetrybreaking to the supersymmetric Standard Model Lagrangian. The source of SUSY breaking results from a different...
O(N) global symmetry is no longer manifest, leaving only the subgroup O(N − 1). The larger symmetry before spontaneous symmetrybreaking is said to be...
2!. The total symmetry factor is 2, and the contribution of this diagram is divided by 2. The symmetry factor theorem gives the symmetry factor for a general...
functions in quantum field theory. It is also important in spontaneous symmetrybreaking. Examples are: The Higgs field has a vacuum expectation value of 246...
less symmetry than the theory allows, and one says that spontaneous symmetrybreaking has occurred. See Higgs mechanism, standard model. Quantum corrections...
temperature, the field causes spontaneous symmetrybreaking during interactions. The breaking of symmetry triggers the Higgs mechanism, causing the bosons...
property by explicitsymmetrybreaking. The calculation of the mean field with self-consistent methods (e.g. Hartree-Fock), breaks rotational symmetry, and the...
pions or kaons, which are the Goldstone bosons of spontaneous chiral symmetrybreaking. The expansion parameter is the pion energy/momentum. For hadrons...
Boyer showed in his work published in 1968 that a conductor with spherical symmetry will also show this repulsive force, and the result is independent of radius...
Charge, parity, and time reversal symmetry is a fundamental symmetry of physical laws under the simultaneous transformations of charge conjugation (C)...
1962. Bibcode:1962JMP.....3.1191D. doi:10.1063/1.1703862. ISSN 0022-2488. Symmetry groups in nuclear and particle physics: a lecture-note and reprint volume...
make the Wightman axioms inappropriate for the case of spontaneous symmetrybreaking because we can always restrict ourselves to a superselection sector...
classical potential, making it important for studying spontaneous symmetrybreaking. It was first defined perturbatively by Jeffrey Goldstone and Steven...
The 1964 PRL symmetrybreaking papers were written by three teams who proposed related but different approaches to explain how mass could arise in local...
finite, but undetermined, coefficient. Other principles, such as gauge symmetry, must then be used to reduce or eliminate the ambiguity. Julian Schwinger...
So the Hamiltonian is different in different frames, and this type of symmetry is not apparent in the original formulation of quantum mechanics. The Hamiltonian...
important applications in physics. For example, in case of explicitsymmetrybreaking, the symmetry group of the problem is reduced from the whole group to...
line is gauge fixing. Drawing the line spoils the gauge symmetry, i.e., the circular symmetry U(1) of the cross section at each point of the rod. The...
classical theory, while attempting to preserve the formal structure, such as symmetries, of the classical theory to the greatest extent possible. Historically...