8,177 research outputs found
U(1) Chiral Gauge Theory with Domain Wall Fermions and Gauge Fixing
We investigate a U(1) lattice chiral gauge theory with the waveguide
formulation of the domain wall fermions and with compact gauge fixing. In the
reduced model limit, there seems to be no mirror chiral modes at the waveguide
boundary.Comment: LATTICE99 (chiral gauge theories), 3 pages, 3 figure
On the continuum limit of gauge-fixed compact U(1) lattice gauge theory
We investigate the continuum limit of a compact formulation of the lattice
U(1) gauge theory in 4 dimensions using a nonperturbative gauge-fixed
regularization. We find clear evidence of a continuous phase transition in the
pure gauge theory for all values of the gauge coupling (with gauge symmetry
restored). When probed with quenched staggered fermions with U(1) charge, the
theory clearly has a chiral transition for large gauge couplings. We identify
the only possible region in the parameter space where a continuum limit with
nonperturbative physics may appear.Comment: latex, 9 pages, 7 figures. Version accepted for publication in Phys.
Lett.
Fermion-Higgs model with strong Wilson-Yukawa coupling in two dimensions
The fermion mass spectrum is studied in the quenched approximation in the
strong coupling vortex phase (VXS) of a globally U(1)U(1)
symmetric scalar-fermion model in two dimensions. In this phase fermion
doublers can be completely removed from the physical spectrum by means of a
strong Wilson-Yukawa coupling. The lowest lying fermion spectrum in this phase
consists most probably only of a massive Dirac fermion which has charge zero
with respect to the group. We give evidence that the fermion which is
charged with respect to that subgroup is absent in the VXS phase. When the
gauge fields are turned on, the neutral fermion may couple chirally to
the massive vector boson state in the confinement phase. The outcome is very
similar to our findings in the strong coupling symmetric phase (PMS) of
fermion-Higgs models with Wilson-Yukawa coupling in four dimensions, with the
exception that in four dimensions the neutral fermion does most probably
decouple from the bosonic bound states.Comment: 21 pages, 6 postscript figures (appended), Amsterdam ITFA 92-21, HLRZ
J\"ulich 92-5
Chiral Gauge Theory on Lattice with Domain Wall Fermions
We investigate a U(1) lattice chiral gauge theory with domain wall fermions
and compact gauge fixing. In the reduced model limit, our perturbative and
numerical investigations show that there exist no extra mirror chiral modes.
The longitudinal gauge degrees of freedom have no effect on the free domain
wall fermion spectrum consisting of opposite chiral modes at the domain wall
and at the anti-domain wall which have an exponentially damped overlap.Comment: 16 pages revtex, 5 postscript figures, PRD versio
Computable randomness is about more than probabilities
We introduce a notion of computable randomness for infinite sequences that
generalises the classical version in two important ways. First, our definition
of computable randomness is associated with imprecise probability models, in
the sense that we consider lower expectations (or sets of probabilities)
instead of classical 'precise' probabilities. Secondly, instead of binary
sequences, we consider sequences whose elements take values in some finite
sample space. Interestingly, we find that every sequence is computably random
with respect to at least one lower expectation, and that lower expectations
that are more informative have fewer computably random sequences. This leads to
the intriguing question whether every sequence is computably random with
respect to a unique most informative lower expectation. We study this question
in some detail and provide a partial answer
Hyperglycemic diet and training alter insulin sensitivity, intramyocellular lipid content but not UCP3 protein expression in rat skeletal muscles
Intramyocellular lipids (IMCL) and mitochondrial uncoupling protein-3 (UCP3) have been implicated in the development of muscular insulin resistance. This study aimed to investigate the role of IMCL and UCP3 in the development of glucose intolerance and muscular insulin resistance during 12 weeks of an obesity-inducing 'cafeteria-style' diet alone (CAF), or in conjunction with exercise training from weeks 8-12 (CAFTR), in rats. At the end of the intervention period, gain in body weight was 20% higher in CAF (305+/-10 g) than controls (CON) (255+/-14 g; p<0.001) and CAFTR (253+/-7 g; p<0.001). Furthermore, compared with CON, the Matsuda insulin sensitivity index (ISI), assessed during a 2-h intravenous glucose tolerance test, was markedly lower in CAF (6.7+/-0.4) than in either CON (15.6+/-1.4; p<0.001) or CAFTR (11.2+/-1.1; p<0.001). Moreover, in CAF glucose transport at a submaximal insulin concentration (200 microU/ml) was reduced by approximately 60% (p<0.05) in both red and white gastrocnemius muscles, but not in m. soleus. However, glucose transport in CAFTR was similar to CON in red gastrocnemius. In CAF fiber-specific IMCL content determined in m. soleus and extensor digitorum longus (EDL), was higher than in CON (p<0.01) and CAFTR (p<0.001). Muscle UCP3 protein content was not changed by any of the interventions. Interestingly, within CAF and CAFTR, ISI closely negatively correlated with IMCL content in both type I (soleus, r=-0.93; EDL, r=-0.90; p<0.05) and IIa (EDL, r=-0.52, p<0.05) muscle fibers. These findings indicate that changes in IMCL content but not UCP3 content are implicated in short-term effects of cafeteria-style diet and exercise training on muscular insulin sensitivity in rats
Strongly coupled U(1) lattice gauge theory as a microscopic model of Yukawa theory
Dynamical chiral symmetry breaking in a strongly coupled U(1) lattice gauge
model with charged fermions and scalar is investigated by numerical simulation.
Several composite neutral states are observed, in particular a massive fermion.
In the vicinity of the tricritical point of this model we study the effective
Yukawa coupling between this fermion and the Goldstone boson. The perturbative
triviality bound of Yukawa models is nearly saturated. The theory is quite
similar to strongly coupled Yukawa models for sufficiently large coupling
except the occurrence of an additional state -- a gauge ball of mass about half
the mass of the fermion.Comment: 4 page
Connie Myers v. Albertsons, Inc. : Brief of Appellee
Appeal of the Judgment of Michael Glasmann Based upon a Jury Verdict Second Judicial District Court Weber County, State of Uta
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