Dynamical gluon mass generation from < A(mu)(2)> in linear covariant gauges

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Minor parties and independents in times of change: Scottish local elections 1974 to 2007

This article explores the electoral performance of minor party and Independent candidates in Scottish local elections from 1974 to 2007. This is a period which began with a major restructuring of local government and ended with a change in the electoral system from first-past-the-post to the single transferable vote. It encompasses a second restructuring in the 1990s, the consolidation of the Scottish National Party as an electoral force, and the creation of the Scottish Parliament. Throughout the period, while there have been ebbs and flows, Independents and minor parties have remained significant players in local electoral politics in Scotland

Is soft breaking of BRST symmetry consistent?

A definition of soft breaking of BRST symmetry in the field-antifield formalism is proposed, valid for general gauge theories and arbitrary gauge fixing. The Ward identities for the generating functionals of Green's functions are derived, and their gauge dependence is investigated. We discuss the Gribov-Zwanziger action for the one-parameter family of R_xi gauges. It is argued that gauge theories with a soft breaking of BRST symmetry are inconsistent.Comment: 1+16 pages; v2: example of section 5 changed to R_xi gauges; v3: small corrections to section 5, one reference added, published versio

The one loop MSbar static potential in the Gribov-Zwanziger Lagrangian

We compute the static potential in the Gribov-Zwanziger Lagrangian as a function of the Gribov mass, gamma, in the MSbar scheme in the Landau gauge at one loop. The usual gauge independent one loop perturbative static potential is recovered in the limit as gamma -> 0. By contrast the Gribov-Zwanziger static potential contains the term gamma^2/(p^2)^2. However, the linearly rising potential in coordinate space as a function of the radial variable r does not emerge due to a compensating behaviour as r -> infty. Though in the short distance limit a dipole behaviour is present. We also demonstrate enhancement in the propagator of the bosonic localizing Zwanziger ghost field when the one loop Gribov gap equation is satisfied. The explicit form of the one loop gap equation for the Gribov mass parameter is also computed in the MOM scheme and the zero momentum value of the renormalization group invariant effective coupling constant is shown to be the same value as that in the MSbar scheme.Comment: 54 latex pages, 6 figures, flaw in original Feynman rules corrected with updated two loop gap equation; new details added on derivation of propagators and their one loop corrections as well as bosonic ghost enhancemen