Showing papers on "Explicit symmetry breaking published in 1984"
CERN1
TL;DR: In this paper, it has been realized that there must be corrections to this simple picture, for example, the meson exchange effects which preclude a simple interpretation of the magnetic moment of the deuteron in terms of d-state probability.
Abstract: Classical nuclear theory deals with a many-body system of neutrons and protons interacting nonrelativistically through two-body potentials. It has, of course, long been realized that there must be corrections to this simple picture—for example, the meson exchange effects which preclude a simple interpretation of the magnetic moment of the deuteron in terms of d-state probability. Nevertheless, the availability of beams of pions, and the consequent ability to study the excitation of real isobars in nuclei, has been critical in the realization that for many problems one must develop a theoretical model which explicitly includes pion and isobar degrees of freedom (see, for example, the proceedings of recent topical conferences Cat+ 82, MT 80).
428 citations
TL;DR: In this paper, a grand unified theory is presented in which all dimensional constants (masses and Newton's gravitational constant) arise due to spontaneous symmetry breaking, and the necessary smallness of the amplitude of adiabatic perturations results from the small value of the grand unification energy as compared to Planck's mass, so the introduction of small coupling constants is not required.
295 citations
TL;DR: In this article, a GUT model is proposed in which the observed CP violation is due to spontaneous symmetry breakdown, and the effective field theory below the GUT scale is simply the standard model.
285 citations
TL;DR: In this paper, a rotational analog of the vibrational potential energy surface is introduced for describing the rotational fine structure of polyatomic molecules, and trajectories on rotational energy surfaces are related to quantum rotational eigenvalue structure.
Abstract: A rotational analog of the vibrational potential energy surface is introduced for describing the rotational fine structure of polyatomic molecules. Classical trajectories on rotational energy (RE) surfaces are related to quantum rotational eigenvalue structure. Interpretation of RE surfaces shows how very different types of molecules may undergo dynamical symmetry breaking and a corresponding clustering of rotational energy sublevels for high angular momentum (J>10). Cluster splitting and spacing are calculated using semiclassical quantization methods. Some consequences of dynamical symmetry breaking such as mixing of nuclear spin species are discussed qualitatively.
178 citations
TL;DR: In this paper, the authors derived the renormalized gap equation from the Dyson equation for the vector and axial-vector vertices of a non-normal-ordered Coulomb gauge hamiltonian, while disagreeing with the gap equation obtained by Finger and Mandula using a normal ordering prescription.
149 citations
TL;DR: In this article, the complete one-fermion loop contribution to the O(∂φ)4 term in the effective lagrangian of the linear SU(2) × SU( 2) σ-model was calculated.
114 citations
TL;DR: In this paper, the influence of the choice of the interpolating field and of the factorization hypothesis for the four quark condensate was investigated and the results were consistent with those obtained from pseudoscalar sum rules and PCAC.
Abstract: We analyse baryonic sum rules in order to determine chiral symmetry breaking condensates. We especially investigate the influence of the choice of the interpolating field and of the factorization hypothesis for the four quark condensate. Our results are consistent with those obtained from pseudoscalar sum rules and PCAC.
109 citations
TL;DR: In this paper, the authors applied low-order spin-wave analysis to the antiferromagnetic plane rotator model on the triangular lattice in order to study the low-temperature properties in the presence of magnetic fields.
Abstract: Lowest-order spin-wave analysis is applied to the antiferromagnetic plane rotator model on the triangular lattice in order to study the low-temperature properties in the presence of magnetic fields. Equilibrium spin configuration in the zero-temperature limit is calculated as a function of the magnetic field. It is found that the thermal-fluctuation effect reduces a continuous degeneracy of the ground state to a discrete one at non-zero temperatures.
69 citations
TL;DR: In this paper, a new O(n)-invariant exactly integrable model was proposed and investigated, and the model was found to undergo dynamical symmetry breaking and hence contain quantum-kink excitations.
66 citations
TL;DR: In this article, the Nambu and Jona-Lasinio model was used as a QCD-motivated effective lagrangian for the chiral symmetry breaking.
59 citations
TL;DR: In this article, a quantum mechanical theory is described (and solved) in which supersymmetry is broken by quantum effects, and the breaking is caused by a singular potential and the ground state energy is nonzero and negative.
TL;DR: In this paper, it was shown that a Killing vector of the kinetic energy metric of a classical mechanical system can generate a symmetry of the system, and thus a constant of the motion.
TL;DR: The first unambiguous demonstration of spontaneous chiral symmetry breaking in lattice-regularized quenched QCD was given in this paper, where the chiral condensate was calculated for all quark masses using Kogut-Susskind fermions.
TL;DR: In this article, the Coleman-Weinberg mechanism of symmetry breaking in a Bianchi type-I universe is investigated, and the one-loop effective potential for a ${\ensuremath{\varphi}}^{4}$ theory and for scalar electrodynamics is calculated by the $\ensureMath{\zeta}$-function method.
Abstract: The Coleman-Weinberg mechanism of symmetry breaking in a Bianchi type-I universe is investigated. The one-loop effective potential for a ${\ensuremath{\varphi}}^{4}$ theory and for scalar electrodynamics is calculated by the $\ensuremath{\zeta}$-function method. The result indicates that the symmetry of the theory will be restored in the highly anisotropic, cold, early universe, irrespective of the coupling between the scalar field and the spacetime curvature scalar. This mechanism of the phase transition explains the isotropy of our universe.
CERN1
TL;DR: In this paper, the electroweak gauge group is broken according to a dynamical scenario based on the chiral symmetry breaking of high colour representations, which requires also the existence of elementary Higgs fields.
TL;DR: In this article, the authors analyse the properties of spontaneous symmetry breaking in the presence of external sources, concentrating on the question whether these sources can lead to a change of the vacuum expectation value of the Higgs field.
TL;DR: Chiral symmetry breaking is studied in lattice quantum electrodynamics in the quenched approximation by computer simulation methods in this paper, where the sensitivity of the lattice action to short-distance features of the action is studied by simulating variant gauge actions.
TL;DR: In this paper, the authors developed a new method for the calculation of the effective potential of composite operators, and applied the method to the study of chiral symmetry breaking in an SU(N) color gauge theory with n massless flavors and derived analytically the complete effective potential at two fermion loops.
TL;DR: In this article, the ratio R 1 R 1 2 of chiral symmetry breaking scales for quarks in the l = 1 and l 1 2 representations of SU(2) is computed for the zero temperature theory in the quenched approximation on a 10 4 lattice.
TL;DR: In this paper, the absence of chiral symmetry breaking for sufficiently high temperature (or chemical potential) is rigorously demonstrated in SU(2) lattice gauge theories with massless fermions in any number of dimensions.
Abstract: The absence of chiral symmetry breaking for sufficiently high temperature (or chemical potential) is rigorously demonstrated in SU(2) lattice gauge theories with massless fermions in any number of dimensions.
TL;DR: In this article, the chiral symmetry breaking at finite temperature was analysed in Coulomb gauge QCD, using a suitably renormalised gap equation. But this analysis was restricted to finite temperature.
01 Jan 1984
TL;DR: The light-quark mass differences are calculated in the framework of the Laplace-transform QCD sum rules using an improved parametrization of the hadronic spectral functions and imply a small flavor symmetry breaking in the QCD nonperturbative vacuum.
TL;DR: In this article, the general theory of Fokker-planck equation symmetries and their relation to derived transport theory symmetry is developed, and the theory is compared to the different formulation given by Onsager.
Abstract: The general theory of Fokker–Planck equation symmetries and their relation to derived transport theory symmetries is developed. The property of microscopic reversibility implies a symmetry in the Fokker–Planck equation for processes obeying detailed balance. It is shown that this symmetry is not sufficient to guarantee Onsager reciprocity for the full matrix of transport coefficients. The general transport matrix has broken symmetry. A partial symmetry can be identified. The theory is compared to the different formulation given by Onsager.
TL;DR: In this article, the authors studied the spontaneous symmetry breaking of the left-right (LR) symmetry based on a model with gauge symmetry SU(2)R × SU( 2)L × U(1)B−L that arises when we include quantum corrections to the tree-level Higgs potential.
TL;DR: In this paper, it was shown that the Poincare group is associated with a special relativistic theory as both its global dynamical symmetry group and its geometrical symmetry group, and that the two groups are of equal significance as symmetry groups of their associated theories.
Abstract: This paper addresses the significance of the general class of diffeomorphisms in the theory of general relativity as opposed to the Poincare group in a special relativistic theory. Using Anderson's concept of an absolute object for a theory, with suitable revisions, it is shown that the general group of local diffeomorphisms is associated with the theory of general relativity as its local dynamical symmetry group, while the Poincare group is associated with a special relativistic theory as both its global dynamical symmetry group and its geometrical symmetry group. It is argued that the two groups are of equal significance as symmetry groups of their associated theories.
TL;DR: A renormalization-group analysis of the dynamical symmetry breaking in QCD based on the Nambu-Jona-Lasinio approach was performed in this article, where the mass scale that the fermions acquire in dynamical symmetric breaking can be calculated in terms of the invariant cutoff.
Abstract: We perform a renormalization-group analysis of the dynamical symmetry breaking in QCD based on the Nambu--Jona-Lasinio approach. We show how the mass scale that the fermions acquire in dynamical symmetry breaking can be calculated in terms of the invariant cutoff. We also determine the high-energy behavior of the quark two-point function.
CERN1
TL;DR: In this article, the symmetry breaking patterns for SU(N) gauge theories with Higgs scalars in totally antisymmetric and symmetric representations of degree k are discussed by solving the extremum conditions.
TL;DR: In this paper, an explicit solution for the SU(3) × SU(2) × U(1) invariant stationary point is given, together with the conditions that ensure it to be a minimum.
TL;DR: In this paper, a new method based on a general energy-entropy inequality was developed to rule out spontaneous breaking of symmetries. But the main advantage of this method consists in its clearcut physical significance and its new areas of applicability; in particular, it can handle discrete symmetry groups as well as continuous ones.
Abstract: For quantum systems we develop a new method, based on a general energy‐entropy inequality, to rule out spontaneous breaking of symmetries. The main advantage of our scheme consists in its clear‐cut physical significance and its new areas of applicability; in particular we can handle discrete symmetry groups as well as continuous ones. Finally a few illustrations are discussed.
TL;DR: In this article, the effective lagrangian for a theory with spontaneous broken gauge symmetry in the presence of an external magnetic field and at high temperature is calculated and the possibility of symmetry restoration is discussed.