954 research outputs found
Two observers calculate the trace anomaly
We adapt a calculation due to Massacand and Schmid to the coordinate
independent definition of time and vacuum given by Capri and Roy in order to
compute the trace anomaly for a massless scalar field in a curved spacetime in
1+1 dimensions. The computation which requires only a simple regulator and
normal ordering yields the well-known result in a
straightforward manner.Comment: RevTeX, 13 pages, some typos corrected and an appendix added, this is
the version to appear in Class. and Quantum Gavit
Massive particle creation in a static 1+1 dimensional spacetime
We show explicitly that there is particle creation in a static spacetime.
This is done by studying the field in a coordinate system based on a physical
principle which has recently been proposed. There the field is quantized by
decomposing it into positive and negative frequency modes on a particular
spacelike surface. This decomposition depends explicitly on the surface where
the decomposition is performed, so that an observer who travels from one
surface to another will observe particle production due to the different vacuum
state.Comment: 17 pages, RevTeX, no figure
Gribov horizon and non-perturbative BRST symmetry in the maximal Abelian gauge
The non-perturbative nilpotent exact BRST symmetry of the Gribov-Zwanziger
action in the Landau gauge constructed in [ arXiv:1506.06995 [hep-th]] is
generalized to the case of Euclidean Yang-Mills theories quantized in the
maximal Abelian gauge. The resulting diagonal gluon propagator is evaluating in
dimensions D=4,3,2. In D=4,3 a decoupling type behavior is found in the
infrared region, while in D=2 a scaling type behavior emerges.Comment: Reviewed version with a new section and new references adde
Interpolating among the Landau, Coulomb and maximal Abelian gauges
A generalized gauge fixing which interpolates among the Landau, Coulomb and
maximal Abelian gauges is constructed.Comment: Final version, to appear in Rapid Communication in Physical Review D.
Added remarks and reference
A non-perturbative study of matter field propagators in Euclidean Yang-Mills theory in linear covariant, Curci-Ferrari and maximal Abelian gauges
In this work, we study the propagators of matter fields within the framework
of the Refined Gribov-Zwanziger theory, which takes into account the effects of
the Gribov copies in the gauge-fixing quantization procedure of Yang-Mills
theory. In full analogy with the pure gluon sector of the Refined
Gribov-Zwanziger action, a non-local long-range term in the inverse of the
Faddeev-Popov operator is added in the matter sector. Making use of the recent
BRST invariant formulation of the Gribov-Zwanziger framework achieved in [Capri
et al 2016], the propagators of scalar and quark fields in the adjoint and
fundamental representations of the gauge group are worked out explicitly in the
linear covariant, Curci-Ferrari and maximal Abelian gauges. Whenever lattice
data are available, our results exhibit good qualitative agreement.Comment: 27 pages, no figures; V2, minor modifications, to appear in EPJ
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