131 research outputs found
To what extent is Gluon Confinement an empirical fact?
Experimental verifications of Confinement in hadron physics have established
the absence of charges with a fraction of the electron's charge by studying the
energy deposited in ionization tracks at high energies, and performing Millikan
experiments with charged droplets at rest. These experiments test only the
absence of particles with fractional charge in the asymptotic spectrum, and
thus "Quark" Confinement. However what theory suggests is that Color is
confined, that is, all asymptotic particles are color singlets. Since QCD is a
non-Abelian theory, the gluon force carriers (indirectly revealed in hadron
jets) are colored. We empirically examine what can be said about Gluon
Confinement based on the lack of detection of appropriate events, aiming at an
upper bound for high-energy free-gluon production.Comment: 14 pages, 12 figures, version accepted at Few Body Physic
Rotationally invariant proof of Bell's theorem without inequalities
The singlet state of two spin-3/2 particles allows a proof of Bell's theorem
without inequalities with two distinguishing features: any local observable can
be regarded as an Einstein-Podolsky-Rosen element of reality, and the
contradiction with local realism occurs not only for some specific local
observables but for any rotation whereof.Comment: REVTeX4, 3 page
Coulomb Gauge QCD, Confinement, and the Constituent Representation
Quark confinement and the genesis of the constituent quark model are examined
in nonperturbative QCD in Coulomb gauge. We employ a self-consistent method to
construct a quasiparticle basis and to determine the quasiparticle interaction.
The results agree remarkably well with lattice computations. They also
illustrate the mechanism by which confinement and constituent quarks emerge,
provide support for the Gribov-Zwanziger confinement scenario, clarify several
perplexing issues in the constituent quark model, and permit the construction
of an improved model of low energy QCD.Comment: 43 pages, 14 figures, revtex, uses psfig.st
quasiharmonic equations of state for dynamically-stabilized soft-mode materials
We introduce a method for treating soft modes within the analytical framework
of the quasiharmonic equation of state. The corresponding double-well
energy-displacement relation is fitted to a functional form that is harmonic in
both the low- and high-energy limits. Using density-functional calculations and
statistical physics, we apply the quasiharmonic methodology to solid periclase.
We predict the existence of a B1--B2 phase transition at high pressures and
temperatures
Nonperturbative Renormalization and the QCD Vacuum
We present a self consistent approach to Coulomb gauge Hamiltonian QCD which
allows one to relate single gluon spectral properties to the long range
behavior of the confining interaction. Nonperturbative renormalization is
discussed. The numerical results are in good agreement with phenomenological
and lattice forms of the static potential.Comment: 23 pages in RevTex, 4 postscript figure
Hilbert Lattice Equations
There are five known classes of lattice equations that hold in every infinite
dimensional Hilbert space underlying quantum systems: generalised
orthoarguesian, Mayet's E_A, Godowski, Mayet-Godowski, and Mayet's E equations.
We obtain a result which opens a possibility that the first two classes
coincide. We devise new algorithms to generate Mayet-Godowski equations that
allow us to prove that the fourth class properly includes the third. An open
problem related to the last class is answered. Finally, we show some new
results on the Godowski lattices characterising the third class of equations.Comment: 24 pages, 3 figure
Spontaneous chiral symmetry breaking in the linked cluster expansion
We investigate dynamical chiral symmetry breaking in the Coulomb gauge
Hamiltonian QCD. Within the framework of the linked cluster expansion we extend
the BCS ansatz for the vacuum and include correlation beyond the
quark-antiquark paring. In particular we study the effects of the three-body
correlations involving quark-antiquark and transverse gluons. The high momentum
behavior of the resulting gap equation is discussed and numerical computation
of the chiral symmetry breaking is presented.Comment: 13 pages, 9 figure
Synchronization and resonance in a driven system of coupled oscillators
We study the noise effects in a driven system of globally coupled
oscillators, with particular attention to the interplay between driving and
noise. The self-consistency equation for the order parameter, which measures
the collective synchronization of the system, is derived; it is found that the
total order parameter decreases monotonically with noise, indicating overall
suppression of synchronization. Still, for large coupling strengths, there
exists an optimal noise level at which the periodic (ac) component of the order
parameter reaches its maximum. The response of the phase velocity is also
examined and found to display resonance behavior.Comment: 17 pages, 3 figure
Phase synchronization and noise-induced resonance in systems of coupled oscillators
We study synchronization and noise-induced resonance phenomena in systems of
globally coupled oscillators, each possessing finite inertia. The behavior of
the order parameter, which measures collective synchronization of the system,
is investigated as the noise level and the coupling strength are varied, and
hysteretic behavior is manifested. The power spectrum of the phase velocity is
also examined and the quality factor as well as the response function is
obtained to reveal noise-induced resonance behavior.Comment: to be published in Phys. Rev.
Astroparticle Physics with a Customized Low-Background Broad Energy Germanium Detector
The MAJORANA Collaboration is building the MAJORANA DEMONSTRATOR, a 60 kg
array of high purity germanium detectors housed in an ultra-low background
shield at the Sanford Underground Laboratory in Lead, SD. The MAJORANA
DEMONSTRATOR will search for neutrinoless double-beta decay of 76Ge while
demonstrating the feasibility of a tonne-scale experiment. It may also carry
out a dark matter search in the 1-10 GeV/c^2 mass range. We have found that
customized Broad Energy Germanium (BEGe) detectors produced by Canberra have
several desirable features for a neutrinoless double-beta decay experiment,
including low electronic noise, excellent pulse shape analysis capabilities,
and simple fabrication. We have deployed a customized BEGe, the MAJORANA
Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and
shield at the Kimballton Underground Research Facility in Virginia. This paper
will focus on the detector characteristics and measurements that can be
performed with such a radiation detector in a low-background environment.Comment: Submitted to NIMA Proceedings, SORMA XII. 9 pages, 4 figure
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