1,317 research outputs found
The quantum bialgebra associated with the eight-vertex R-matrix
The quantum bialgebra related to the Baxter's eight-vertex R-matrix is found
as a quantum deformation of the Lie algebra of sl(2)-valued automorphic
functions on a complex torus.Comment: 4 page
Comparing Robustness of Pairwise and Multiclass Neural-Network Systems for Face Recognition
Noise, corruptions and variations in face images can seriously hurt the
performance of face recognition systems. To make such systems robust,
multiclass neuralnetwork classifiers capable of learning from noisy data have
been suggested. However on large face data sets such systems cannot provide the
robustness at a high level. In this paper we explore a pairwise neural-network
system as an alternative approach to improving the robustness of face
recognition. In our experiments this approach is shown to outperform the
multiclass neural-network system in terms of the predictive accuracy on the
face images corrupted by noise
Flexoelectricity and apparent piezoelectricity of a pantographic micro-bar
We discuss a homogenized model of a pantographic bar considering flexoelectricity. A pantographic bar consists of relatively stiff small bars connected by small soft flexoelectric pivots. As a result, an elongation of the bar relates almost to the torsion of pivots. Taking into account their flexoelectric properties we find the corresponding electric polarization. As a results, the homogenized pantographic bar demonstrates piezoelectric properties inherited from the flexoelectric properties of pivots. The effective stiffness properties of the homogenized bars are determined by the geometry of the structural elements and shear stiffness whereas the piezoelectric properties follow from the flexoelectric moduli of the pivots
The structure of quotients of the Onsager algebra by closed ideals
We study the Onsager algebra from the ideal theoretic point of view. A
complete classification of closed ideals and the structure of quotient algebras
are obtained. We also discuss the solvable algebra aspect of the Onsager
algebra through the use of formal Lie algebras.Comment: 33 pages, Latex, small topos corrected-Journal versio
Boundary K-matrices for the XYZ, XXZ AND XXX spin chains
The general solutions for the factorization equations of the reflection
matrices for the eight vertex and six vertex models (XYZ, XXZ
and XXX chains) are found. The associated integrable magnetic Hamiltonians are
explicitly derived, finding families dependig on several continuous as well as
discrete parameters.Comment: 13 page
Cr/Sc multilayer radiator for parametric EUV radiation in "water-window" spectral range
The results of experimental investigation of parametric radiation generated by 5.7 MeV electrons in a multilayer structure consisting of 100 Cr/Sc bi-layers deposited on a Si3N4 membrane are presented. The multilayer structure was specially created for generation of parametric radiation with photon energy in "water-window" spectral rang
Observation of soft X-ray Cherenkov radiation in Al
The soft X-ray radiation generated by 5.7 MeV electrons from both an Al foil and a Mylar film in forward direction was experimentally studied. A narrow specific directivity, an ultra-narrow spectral bandwidth and a good consistency between the experiment and theory prove that the Cherenkov radiation (CR) with photon energy near the L-edge of absorption in Al was observed. The results demonstrate that the CR spectral-angular properties and the absolute photon yield can be described well enough using Pafomov's theoretical model and Henke's refractive index database, which is essential for all practical applications
sl(N) Onsager's Algebra and Integrability
We define an analog of Onsager's Algebra through a finite set of
relations that generalize the Dolan Grady defining relations for the original
Onsager's Algebra. This infinite-dimensional Lie Algebra is shown to be
isomorphic to a fixed point subalgebra of Loop Algebra with respect
to a certain involution. As the consequence of the generalized Dolan Grady
relations a Hamiltonian linear in the generators of Onsager's Algebra
is shown to posses an infinite number of mutually commuting integrals of
motion
Collective Field Description of Spin Calogero-Sutherland Models
Using the collective field technique, we give the description of the spin
Calogero-Sutherland Model (CSM) in terms of free bosons. This approach can be
applicable for arbitrary coupling constant and provides the bosonized
Hamiltonian of the spin CSM. The boson Fock space can be identified with the
Hilbert space of the spin CSM in the large limit. We show that the
eigenstates corresponding to the Young diagram with a single row or column are
represented by the vertex operators. We also derive a dual description of the
Hamiltonian and comment on the construction of the general eigenstates.Comment: 14 pages, one figure, LaTeX, with minor correction
Conformal field theory and edge excitations for the principal series of quantum Hall fluids
Motivated by recent experimental results, we reconsider the theory of the
edge excitations for the fractional Hall effect at filling factors
. We propose to modify the standard edge
theory for this series by introducing twist fields which change the boundary
conditions of the bosonic fields and simulate the effect of fractions of flux
quanta . This has the effect of removing the conserved charges
associated to the neutral modes while keeping the right statistics of the
particles. The Green function of the electron in presence of twists decays at
long distance with an exponent varying continuously with .Comment: 5 pages, latex; typos corrected and some references adde
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