7,411 research outputs found
Confinement by Monopoles in the Positive Plaquette Model of SU(2) Lattice Gauge Theory
Confinement via 't Hooft-Mandelstam monopoles is studied for the positive
plaquette model in SU(2) lattice gauge theory. Positive plaquette model
configurations are projected into the maximum abelian gauge and the magnetic
current extracted. The resulting magnetic current is used to compute monopole
contributions to Wilson loops and extract a monopole contribution to the string
tension. As was previously found for the Wilson action, the monopole
contribution to the string tension agrees with the string tension calculated
directly from the SU(2) links. The fact that the positive plaquette model
suppresses Z2 monopoles and vortices is discussed.Comment: 8 pages, one Postscript figure, Latex, uses psfig files:
posplaq.tex,posplaq.aux,pp_1_3.ps packaged with uufile
Jettisoning system for a parachute's canister
Three-point automatically released suspension and jettisoning system operates independently of lander's power system and releases parachute on touchdown. The system is based on a ball-lock device operated by the shock of the parachute's opening and by the subsequent decay in the load on the main cord
Separation of two bodies in space. A machine programmed analysis using the Lagrange equations and Eulerian angles
Fortran computer program and Lagrangian motion equations for separation analysis of two bodies in spac
Neural multigrid for gauge theories and other disordered systems
We present evidence that multigrid works for wave equations in disordered
systems, e.g. in the presence of gauge fields, no matter how strong the
disorder, but one needs to introduce a "neural computations" point of view into
large scale simulations: First, the system must learn how to do the simulations
efficiently, then do the simulation (fast).
The method can also be used to provide smooth interpolation kernels which are
needed in multigrid Monte Carlo updates.Comment: 9 pages [2 figures appended in PostScript format], preprint DESY
92-126, Sept. 199
A practical low-boom overpressure signature based on minimum sonic boom theory
A brief resume of sonic boom minimization methods is given to provide a background for a new, empirical modification of the Seebass and George minimum-nose-shock sonic boom F-function and signature. The new 'hybrid' F-function has all the inherent flexibility of application found with the Darden-modified Seebass and George F-function. In addition, it has enhanced this flexibility and applicability with neglegible increase in nose and/or tail shock strength. A description of this 'hybrid' F-function and signature is provided, and the benefits of using them to design high-performance, low-boom aircraft are discussed
Separation of two bodies in space
Computer program analyzes the motion of two rigid bodies in space, separating as a result of any one, or a combination of, the following mechanisms - springs with ball ends, springs with one end guided, pyrotechnics, rockets, cold-gas jets, air pistons, and Coulomb drag
Free energy of an SU(2) monopole-antimonopole pair
We induce an external monopole-antimonopole pair in an SU(2) lattice
gauge system and measure its free energy as a way to probe the vacuum
structure. We discuss the motivation and computational methodology of the
investigation and illustrate our preliminary results.Comment: LATTICE98(confine
Vortex dominance of the 0+ and 2+ glueball mass in SU(2) lattice gauge theory
The c-vortex ensembles are constructed by means of the recently proposed
cooling method which gradually removes the SU(2)/Z_2 coset fields from the
SU(2) lattice configurations and which thus reveals the Z_2 vortex vacuum
texture. Using Teper's blocking method, the screening masses of the 0+ and the
2+ glueball is calculated from these vortex ensembles and compared with the
masses obtained from full configurations. The masses of either case agree
within the achieved numerical accuracy of 10%. As a byproduct, we find that the
overlaps of the Teper operators with the glueball wavefunctions are
significantly larger in the case of the c-vortex ensembles.Comment: 9 pages, 4 PS figures, LaTeX using eps
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