161 research outputs found
Analysis and design of space vehicle flight control systems. Volume XIII - Adaptive control
Mathematical models used for space vehicle flight adaptive control system
Analysis and design of space vehicle flight control systems. Volume 16 - Abort
Manned spacecraft control system requirements for abort problem
Analysis and design of space vehicle flight control systems. Volume XII - Attitude control in space
Analysis and design of attitude control systems for earth orbiting satellit
Analysis and design of space vehicle flight control systems. Volume XV - Elastic body equations
Elastic body equations in analysis and design of space vehicle flight control system
Analysis and design of space vehicle flight control systems. Volume VII - Attitude control during launch
Analysis and design of space vehicle control systems - short period dynamics of attitude control during launch and autopilot desig
Analysis and design of space vehicle flight control systems. Volume II - Trajectory equations
Trajectory equations describing spacecraft motion from launch to earth impact or orbit injectio
Analysis and design of space vehicle flight control systems. Volume VI - Stochastic effects
Statistical methods for analyzing stochastic effects influencing design of space vehicle control system
Creutz Ratios From Color-Truncated Lattice Configurations
We investigate whether information about Creutz ratios is encoded,
separately, in each gluon color component of numerically generated lattice
configurations. Working in SU(2) lattice gauge theory in Landau gauge, we set
two of the three gluon color components to zero, and compensate for the loss of
two-thirds of the fluctuation by simply rescaling the remaining component by a
factor of . Creutz ratios are then computed with this "abelianized"
configuration. We find that the Creutz ratios of loops constructed from
abelianized links converge to the usual Creutz ratios in the scaling regime.Comment: 5 pages, plain LaTeX, one figur
Remarks on abelian dominance
We used a renormalisation group based smoothing to address two questions
related to abelian dominance. Smoothing drastically reduces short distance
fluctuations but it preserves the long distance physical properties of the
SU(2) configurations. This enabled us to extract the abelian heavy-quark
potential from time-like Wilson loops on Polyakov gauge projected
configurations. We obtained a very small string tension which is inconsistent
with the string tension extracted from Polyakov loop correlators. This shows
that the Polyakov gauge projected abelian configurations do not have a
consistent physical meaning. We also applied the smoothing on SU(2)
configurations to test how sensitive abelian dominance in the maximal abelian
gauge is to the short distance fluctuations. We found that on smoothed SU(2)
configurations the abelian string tension was about 30% smaller than the SU(2)
string tension which was unaffected by smoothing. This suggests that the
approximate abelian dominance found with the Wilson action is probably an
accident and it has no fundamental physical relevance.Comment: 13 pages, LaTeX, 3 eps figure
The Gribov horizon and the one-loop color-Coulomb potential
We recalculate the color-Coulomb potential to one-loop order, under the
assumption that the effect of the Gribov horizon is to make i) the transverse
gluon propagator less singular; and ii) the color-Coulomb potential more
singular, than their perturbative behavior in the low-momentum limit. As a
first guess, the effect of the Gribov horizon is mimicked by introducing a
transverse momentum-dependent gluon mass term, leading to a propagator of the
Gribov form, with the prescription that the mass parameter should be adjusted
to the unique value where the infrared behavior of the Coulomb potential is
enhanced. We find that this procedure leads to a Coulomb potential rising
asymptotically as a linear term modified by a logarithm.Comment: 15 pages, 2 figure
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