82 research outputs found
A Testbed About Priority-Based Dynamic Connection Profiles in QoS Wireless Multimedia Networks
The ever-growing demand of high-quality broadband connectivity in mobile scenarios, as well as the Digital Divide discrimination, are boosting the development of more and more efficient wireless technologies.
Despite their adaptability and relative small installation costs, wireless networks still lack a full bandwidth availability and are also subject to interference problems.
In context of a Metropolitan Area Network serving a large number of users, a bandwidth increase can turn out to be neither feasible nor justified. In consequence, and in order to
meet the needs of multimedia applications, bandwidth optimization techniques were designed and developed, such as Traffic Shaping, Policy-Based Traffic Management and Quality of Service (QoS).
In this paper, QoS protocols are adopted and, in particular, priority-based dynamic profiles in a QoS wireless multimedia network. This technique allows to asssign different priorities to distinct applications, so as to rearrange service quality in a dynamic way and guarantee the desired performance to a given data flow
Wigner Oscillators, Twisted Hopf Algebras and Second Quantization
By correctly identifying the role of central extension in the centrally
extended Heisenberg algebra h, we show that it is indeed possible to construct
a Hopf algebraic structure on the corresponding enveloping algebra U(h) and
eventually deform it through Drinfeld twist. This Hopf algebraic structure and
its deformed version U^F(h) are shown to be induced from a more fundamental
Hopf algebra obtained from the Schroedinger field/oscillator algebra and its
deformed version, provided that the fields/oscillators are regarded as
odd-elements of the super-algebra osp(1|2n). We also discuss the possible
implications in the context of quantum statistics.Comment: 23 page
Lie-Algebraic Characterization of 2D (Super-)Integrable Models
It is pointed out that affine Lie algebras appear to be the natural
mathematical structure underlying the notion of integrability for
two-dimensional systems. Their role in the construction and classification of
2D integrable systems is discussed. The super- symmetric case will be
particularly enphasized. The fundamental examples will be outlined.Comment: 6 pages, LaTex, Talk given at the conference in memory of D.V.
Volkov, Kharkhov, January 1997. To appear in the proceeding
Inequivalent -graded brackets, -bit parastatistics and statistical transmutations of supersymmetric quantum mechanics
Given an associative ring of -graded operators, the number of
inequivalent brackets of Lie-type which are compatible with the grading and
satisfy graded Jacobi identities is . This follows
from the Rittenberg-Wyler and Scheunert analysis of "color" Lie (super)algebras
which is revisited here in terms of Boolean logic gates. The inequivalent
brackets, recovered from mappings, are
defined by consistent sets of commutators/anticommutators describing particles
accommodated into an -bit parastatistics (ordinary bosons/fermions
correspond to bit). Depending on the given graded Lie (super)algebra, its
graded sectors can fall into different classes of equivalence expressing
different types of (para)bosons and/or (para)fermions. As a first application
we construct and -graded quantum Hamiltonians which
respectively admit and inequivalent multiparticle quantizations
(the inequivalent parastatistics are discriminated by measuring the eigenvalues
of certain observables in some given states). As a main physical application we
prove that the -extended, supersymmetric and superconformal quantum
mechanics, for , are respectively described by
alternative formulations based on the inequivalent graded Lie (super)algebras.
These numbers correspond to all possible "statistical transmutations" of a
given set of supercharges which, for , are accommodated into a
-grading with (the identification is ). In the
simplest setting (the -particle sector of the de DFF deformed
oscillator with spectrum-generating superalgebra), the -graded
parastatistics imply a degeneration of the energy levels which cannot be
reproduced by ordinary bosons/fermions statistics.Comment: 57 pages, 16 figure
An Unfolded Quantization for Twisted Hopf Algebras
In this talk I discuss a recently developed "Unfolded Quantization
Framework". It allows to introduce a Hamiltonian Second Quantization based on a
Hopf algebra endowed with a coproduct satisfying, for the Hamiltonian, the
physical requirement of being a primitive element. The scheme can be applied to
theories deformed via a Drinfeld twist. I discuss in particular two cases: the
abelian twist deformation of a rotationally invariant nonrelativistic Quantum
Mechanics (the twist induces a standard noncommutativity) and the Jordanian
twist of the harmonic oscillator. In the latter case the twist induces a Snyder
non-commutativity for the space-coordinates, with a pseudo-Hermitian deformed
Hamiltonian. The "Unfolded Quantization Framework" unambiguously fixes the
non-additive effective interactions in the multi-particle sector of the
deformed quantum theory. The statistics of the particles is preserved even in
the presence of a deformation.Comment: 9 pages. Talk given at QTS7 (7th Int. Conf. on Quantum Theory and
Symmetries, Prague, August 2011
Division Algebras and Extended N=2,4,8 SuperKdVs
The first example of an N=8 supersymmetric extension of the KdV equation is
here explicitly constructed. It involves 8 bosonic and 8 fermionic fields. It
corresponds to the unique N=8 solution based on a generalized hamiltonian
dynamics with (generalized) Poisson brackets given by the Non-associative N=8
Superconformal Algebra. The complete list of inequivalent classes of
parametric-dependent N=3 and N=4 superKdVs obtained from the ``Non-associative
N=8 SCA" is also furnished. Furthermore, a fundamental domain characterizing
the class of inequivalent N=4 superKdVs based on the "minimal N=4 SCA" is
given.Comment: 14 pages, LaTe
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