Showing papers on "Gauge boson published in 1990"
TL;DR: In this paper, closed analytic expressions for the O( αα s ) corrections to the vacuum polarizations of neutral gauge bosons induced by a massive quark and to those of charged bossons associated with a quark isodoublet of large mass splitting are derived through dispersive methods for variable external invariant mass s.
186 citations
TL;DR: In this article, the interaction of point particles in a gauge theory for gravity in 2 + 1 dimensions with particular emphasis on the effects of spin is analyzed, and it is shown that the known space-time solution for spinning sources in Einstein gravity exhibits torsion at the location of the sources.
126 citations
TL;DR: In this paper, the authors studied lattice hamiltonians with continuous local SU(2) gauge invariance, for which the Hilbert space on each link is finite dimensional and the generators of gauge transformations are built out of local spin operators.
125 citations
TL;DR: A grand unified model based on SU(15) is described, where baryon-numbe-violating processes such as proton decay are absent in both the gauge and Higgs sectors and a number of new gauge bosons are predicted at Superconducting Super Collider energy.
Abstract: A grand unified model based on SU(15) is described. Baryon-numbe-violating processes such as proton decay are absent in both the gauge and Higgs sectors. A number of new gauge bosons are predicted at Superconducting Super Collider energy, including doubly charged gauge bosons coupling only to leptons.
116 citations
TL;DR: It is shown how massless Goldstone bosons, not present in the {ital S} matrix, must be introduced into Green's functions in order to reconcile gauge invariance and renormalizability.
Abstract: Using the pinch technique, we show how to recover, from the {ital S} matrix of a spontaneously broken non-Abelian gauge theory, proper self-energies and vertices which are fully gauge invariant when one or more momenta are off shell. Explicit calculations are carried out at the one-loop level for gauge-boson self-energies and fermion--gauge-boson vertices in a simple SU(2) gauge theory with a Higgs boson. The same technique allows us to calculate, at one-loop order, a neutrino electromagnetic form factor which is gauge invariant at all photon momenta, thus resolving a long-standing problem. We show how massless Goldstone bosons, not present in the {ital S} matrix, must be introduced into Green's functions in order to reconcile gauge invariance and renormalizability.
107 citations
TL;DR: In this paper, the authors discuss possible extra U(1) gauge symmetries for extensions of the standard model, in connection with their Higgs boson sectors, and discuss the main physical implications of this analysis.
106 citations
TL;DR: In this paper, the authors examine bosonic zero modes of vortices formed in the gauge breaking G→H. Their solutions depend on global symmetry structure and the resulting superconductivity has novel electrodynamics.
Abstract: We examine bosonic zero modes of vortices formed in the gauge breaking G→H. For non-Abelian G, zero modes are generic. Their solutions depend on global symmetry structure. Vortices render the embedding H⊂G space dependent, with a dynamically determined subgroup H single valued. They Aharonov-Bohm scatter gauge bosons associated with multivalued generators. Alice strings (H=O(2), H=openZ2) attract charges and scatter SO(2) ‘‘photons,’’ and a two-string system has zero modes with unlocalizable ‘‘Cheshire’’ charge. The resulting superconductivity has novel electrodynamics.
79 citations
TL;DR: By numerical simulations of the SU(2) lattice gauge theory, this paper showed that the density of monopoles, which occupy several lattice cells (extended monopoles), is strongly correlated with the string tension during cooling of the gauge fields.
78 citations
TL;DR: In this paper, a globally correct gauge fixing with the feature that the Waard identities express classical gauge invariance instead of BRS invariance was introduced, and an expansion for a confined gluon phase was obtained.
72 citations
TL;DR: In this article, the spontaneous breaking of intermediate-scale gauge symmetries at scale MI or MGUT was shown to cause large contributions to all low-energy scalar masses (squarks, sleptons and higgses) which possess non-vanishing charges under the broken generators.
69 citations
TL;DR: In this paper, the authors explore the phenomenology of a nonstandard electroweak theory in which left-handed quarks and leptons transform as doublets under separate SU(2) gauge groups.
TL;DR: In this paper, a review of formulation and methods of calculation of the parametrization and gauge invariant effective actions in quantum field theory is given, and the dependence of standard EA of composite fields upon the gauge is studied for the general gauge theories.
Abstract: The review of formulation and methods of calculation of the parametrization and gauge invariant effective actions in quantum field theory is given. As an example the Vilkovisky-De Witt Effective action (EA) is studied (this EA is a natural representative of gauge and parametrization invariant EA's). The examples where the use of the standard EA leads to the ambiguity are demonstrated. This happens as the result of dependence of the standard EA upon the choice of gauge condition. These examples are as follows: Coleman-Weinberg potential in the finite theories and symmetry breaking, EA in quantum gravity with matter and d = 5 gauged supergravity, the possibility of spontaneous supersymmetry breaking in N = 1 supergravity and the spontaneous compactification in the multidimensional R2-gravity. In all these cases the one-loop Vilkovisky-De Witt EA is found and therefore the problem of gauge dependence of EA is solved.
The dependence of standard EA of composite fields upon the gauge is studied for the general gauge theories. The class of gauge and parametrization invariant EA's of the composite fields is offered.
TL;DR: Amplitudes for the production of electroweak-gauge-boson pairs (any combination of {gamma}, {ital Z}, or {ital W}{sup {plus minus}}) in association with up to two jets are given in this paper.
Abstract: Amplitudes for the production of electroweak-gauge-boson pairs (any combination of {gamma}, {ital Z}, or {ital W}{sup {plus minus}}) in association with up to two jets are given. The gauge bosons may be either real or virtual with subsequent decays into charged or neutral leptons. The amplitudes are presented in a form directly amenable to numerical evaluation. Representative cross sections are given for Fermilab Tevatron, CERN Large Hadron Collider, and Superconducting Super Collider center-of-mass energies.
TL;DR: In this article, an effective chiral meson lagrangian involving pseudoscalar, vector and axial-vector mesons is presented. But the authors do not consider the effect of the Wess-Zumino-Witten action.
TL;DR: In this paper, the authors derived upper limits of order of a few TeV to the mass of the lightest supersymmetric particle LSP as well as to the masses of new U′(1) gauge bosons and their associated stable electroweak singlets.
01 Sep 1990
TL;DR: In this article, a review of developments in lattice formulations of chiral gauge theories is given, and it is shown that the unwanted fermion doublers can be decoupled satisfactorily by giving them masses of the order of the cutoff.
Abstract: A review is given of developments in lattice formulations of chiral gauge theories. There is now evidence that the unwanted fermion doublers can be decoupled satisfactorily by giving them masses of the order of the cutoff.
TL;DR: In this paper, a proof of renormalizability of a non-riemannian model, based on gauging GL(4, R ), in which Einstein's gravity dominates the low-energy region through a Goldstone-Higgs spontaneous symmetry breakdown mechanism was presented.
TL;DR: In this article, it was shown that no B-violating superpotential interaction arises in flipped SU(5), thanks to an extra symmetry of the effective cubic d=4 and quartic d=5 superpotentials terms, induced at short distances.
TL;DR: In this article, the effect of making the four-fermion approximation of the gap equation in dressed ladder approximation is considered and the solutions ∑t(p) are used to determine the decay constants of the top quark mass.
TL;DR: In this article, the effective action of finite SU(3) gauge theory in a constant diagonal background fieldA 0(t,x)=B 0 3 T3+B 0 8 T8 in the general covariant background gauge up to terms of orderg 3.
Abstract: We compute the effective action of finiteT SU(3) gauge theory in a constant diagonal background fieldA 0(t,x)=B 0 3 T3+B 0 8 T8 in the general covariant background gauge up to terms of orderg 3.B 0 3,8 shield the infrared singularities and the aim is to study whether the minimum of the effective action would determine their values dynamically. We find that the orderg 2 term depends explicitly on the gauge fixing parameter ξ. Since the background field screens already at the tree diagram level the interactions of the six non-diagonal gluon fields they do not contribute to the plasmon-likeg 3 term. The two diagonal fieldsA 0 3 ,A 0 8 do, but the electric mass squared they develop will become negative if the background fields are larger than aboutT/g. Hence large background fields make the system unstable.
TL;DR: In this paper, the authors study gauge boson pair production at future hadron colliders in the presence of a strong interacting electroweak symmetry breaking sector, with parameters limited from presented experiments as well as in view of future attainable LEP precisions.
TL;DR: In this article, the BRST procedure is applied to obtain its gauge-fixed action, which is done in such a way that some components of the gauge potential are identified as the zweibein and the spin connection of the two-dimensional manifold.
TL;DR: In this paper, the authors studied the total cross-section of high energy collisions in the one-instanton sector of purely bosonic theories with instantons, and they showed that the leading behavior of the total total crosssection is σlot ~ exp [1/g2(−2S0 + F(E/Esph))], where S0 is the instanton action.
Abstract: We study the total cross-section of high energy collisions in the one-instanton sector of purely bosonic theories with instantons. We find that in the limit g2 → 0, E/Esph = fixed, the leading behavior of the total cross-section is σlot ~ exp [1/g2(−2S0 + F(E/Esph))], where S0 is the instanton action. In the electroweak theory at E/Esph ≪ 1, the function F(E/Esph) is determined by the gauge boson part of the instanton configuration and its explicit form is found.
TL;DR: Gauge invariance is discussed in the causal approach to QED as mentioned in this paper, and it is proven that the iterative construction of theS-matrix by the method of Epstein and Glaser can be carried out in such a way that perturbative gauge invariance holds true.
Abstract: Gauge invariance is discussed in the causal approach to QED. It is proven that the iterative construction of theS-matrix by the method of Epstein and Glaser can be carried out in such a way that perturbative gauge invariance holds true. The proof rests on a careful analysis of the process of distribution splitting. In case of nontrivial distribution splitting gauge invariance implies the Ward-Takahashi identities.
TL;DR: In this article, the one-loop effective potentials for the non-integrable phases of Wilson lines at both zero and finite temperature were derived using the zeta-function technique.
TL;DR: The phenomenology of baryon-number violation induced by electroweak instantons is studied and it is found that if the naive instanton amplitudes were valid for arbitrarily high energies, the event rate at the Superconducting Super Collider could be a few per hour.
Abstract: We study the phenomenology of baryon-number violation induced by electroweak instantons and find that if the naive instanton amplitudes were valid for arbitrarily high energies, the event rate at the Superconducting Super Collider could be a few per hour. A typical event would consist of three primary'' antileptons and seven primary'' antiquark jets, accompanied by {similar to}85 electroweak gauge bosons, having a sharp threshold in the total subenergy at about 17 TeV. However, the instanton approximation is not valid at such high energy ({ital above} the sphaleron energy), so that new theoretical methods are needed.
TL;DR: In this article, the mass of the heavy particles that mediate their production and rescattering in the stellar medium was studied. But the uncertainties in the parameters of the stellar core were taken into account, and it was shown that the quarks and selectrons of E6 superstring-inspired models must all lie above the one TeV scale.
TL;DR: In this paper, a topological W_3 gravity model is constructed from its definition as topological Yang-Mills theory in two dimensions with the gauge group being a contraction of SL(3, R).
TL;DR: In this article, temperature effects on homogeneous and nonhomogeneous boson condensation in gauge field theories in both abelian and nonabelian cases were studied, and it was found that symmetry restoration can occur at the critical temperature at which the topological solitons vanish.