10,664 research outputs found
Center Vortices at Strong Couplings
A long-range effective action is derived for strong-coupling lattice SU(2)
gauge theory in D=3 dimensions. It is shown that center vortices emerge as
stable saddlepoints of this action.Comment: Lattice 2000 (Topology and Vacuum), 4 page
Asymptotic Scaling, Casimir Scaling, and Center Vortices
We report on two recent developments in the center vortex theory of
confinement: (i) the asymptotic scaling of the vortex density, as measured in
Monte Carlo simulations; and (ii) an explanation of Casimir scaling and the
adjoint string tension, in terms of the center vortex mechanism.Comment: LATTICE98(confine), 3 pages, 3 figure
Rudolf Serkin: A Life
Pianist Rudolf Serkin, a virtuosic solo performer and chamber musician, captivated music lovers the world over for much of the twentieth century. Although he acquired a large and devoted public following, Serkin preferred to keep out of the spotlight, instead directing attention toward the music he loved. Dedicated to disseminating European classical music in America, Serkin became a committed teacher and director of major musical institutions. Rudolf Serkin: A Life, the first biography of this influential figure, offers an insightful analysis of Serkin\u27s role in shaping American musical values and provides a rare glimpse into the life story of this intense performer and elusive man
Unequal Exposure to Ecological Hazards 2005: Environmental Injustices in the Commonwealth of Massachusetts
Unequal Exposure to Ecological Hazards 2005 documents Massachusetts residents' unequal exposure to environmental hazards. More specifically, the report analyzes both income basedand racially-based disparities in the geographic distribution of some 17 different types ofenvironmentally hazardous sites and industrial facilities in the Commonwealth of Massachusetts. This report provides evidence that working class communities and communities of color are disproportionately impacted by toxic waste disposal, incinerators, landfills, trash transfer stations, power plants, and polluting industrial facilities. In some cases, not only are new toxic facilities and dump sites located in poorer neighborhoods and communities of color, but as in the case of the public housing development and playgrounds near the Alewife station in Cambridge, housing for people of color and low income populations is sometimes located on top of preexisting hazardous waste sites and/or nearby polluting facilities. We conclude that striking inequities in the distribution of these environmentally hazardous sites and facilities are placing working class families and people of color at substantially greater risk of exposure to human health risks. We advocate the adoption of a number of measures, including a comprehensive environmental justice act, to reduce pollution and address unequal exposure to ecological threats
What are the Confining Field Configurations of Strong-Coupling Lattice Gauge Theory?
Starting from the strong-coupling SU(2) Wilson action in D=3 dimensions, we
derive an effective, semi-local action on a lattice of spacing L times the
spacing of the original lattice. It is shown that beyond the adjoint
color-screening distance, i.e. for , thin center vortices are stable
saddlepoints of the corresponding effective action. Since the entropy of these
stable objects exceeds their energy, center vortices percolate throughout the
lattice, and confine color charge in half-integer representations of the SU(2)
gauge group. This result contradicts the folklore that confinement in
strong-coupling lattice gauge theory, for D>2 dimensions, is simply due to
plaquette disorder, as is the case in D=2 dimensions. It also demonstrates
explicitly how the emergence and stability of center vortices is related to the
existence of color screening by gluon fields.Comment: 17 pages, 5 figures, latex2
Center Projection With and Without Gauge Fixing
We consider projections of SU(2) lattice link variables onto Z(2) center and
U(1) subgroups, with and without gauge-fixing. It is shown that in the absence
of gauge-fixing, and up to an additive constant, the static quark potential
extracted from projected variables agrees exactly with the static quark
potential taken from the full link variables; this is an extension of recent
arguments by Ambjorn and Greensite, and by Ogilvie. Abelian and center
dominance is essentially trivial in this case, and seems of no physical
relevance. The situation changes drastically upon gauge fixing. In the case of
center projection, there are a series of tests one can carry out, to check if
vortices identified in the projected configurations are physical objects. All
these criteria are satisfied in maximal center gauge, and we show here that
they all fail in the absence of gauge fixing. The non-triviality of center
projection is due entirely to the maximal center gauge-fixing, which pumps
information about the location of extended physical objects into local Z(2)
observables.Comment: 18 pages, 6 figures, Latex2
Evidence for a Center Vortex Origin of the Adjoint String Tension
Wilson loops in the adjoint representation are evaluated on cooled lattices
in SU(2) lattice gauge theory. It is found that the string tension of an
adjoint Wilson loop vanishes, if the loop is evaluated in a sub-ensemble of
configurations in which no center vortex links the loop. This result supports
our recent proposal that the adjoint string tension, in the Casimir-scaling
regime, can be attributed to a center vortex mechanism.Comment: 10 pages, 5 figures, Latex2
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