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1.
B. Enriquez 《Communications in Mathematical Physics》1995,170(1):197-206
We propose a quantum lattice version of B. Feigin and E. Frenkel's constructions, identifying the KdV differential polynomials with functions on a homogeneous space under the nilpotent part of
. We construct an action of the nilpotent part
of
on their lattice counterparts, and embed the lattice variables in a
, coinduced from a quantum version of the principal commutative subalgebra, which is defined using the identification of
with its dual algebra. 相似文献
2.
A natural supersymmetric extension
is defined of the current (= affine Kac-Moody Lie) algebra
; it corresponds to a superconformal and chiral invariant 2-dimensional quantum field theory (QFT), and hence appears as an ingredient in superstring models. All unitary irreducible positive energy representations of
are constructed. They extend to unitary representations of the semidirect sumS
(G) of
with the superconformal algebra of Neveu-Schwarz, for
, or of Ramond, for =0.On leave of absence from the Institute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences, BG-1184 Sofia, Bulgaria 相似文献
3.
We consider the decomposition of the conformal blocks under the conformal embeddings. The case
(â is an affine extension of the abelian subalgebra of the central elements ofgl(lr)) is studied in detal. The reciprocal decompositions of
-modules induce a pairing between the spaces of conformal blocks of
and
Wess-Zumino-Witten models on the Riemann sphere. The completeness of the pairing is shown. Hence it defines aduality between two spaces.Dedicated to Professor Masahisa Adachi on his 60th birthday 相似文献
4.
The authors deal with the tunneling of electrons across an inhomogeneous delta-barrier defined by the potential energy
(where
0$$
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and
0$$
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are two constants). In particular, the perpendicular incidence of an electron with a given value
of the wave vector
is considered. The electron is forward-scattered into the region behind the barrier (region 2:
0$$
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), i. e. the wave function
is composed of plane waves with all wave vectors
such that
and
\left. 0 \right)} $$
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) (where
). Therefore, if
0$$
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, the wave function of the electron is represented as
, where
. An approximate formula is derived for the amplitude
. The authors pay a special attention to the flow density
and calculate this function in two cases: 1. for the plane
and 2. for high values of
is the diffraction angle). The authors discuss the relevance of their diffraction problem in a prospective quantum-mechanical theory of the tunneling of electrons across a randomly inhomogeneous Schottky barrier. 相似文献
5.
J. Donin 《Czechoslovak Journal of Physics》1997,47(11):1115-1122
For
we construct a two parametric
-invariant family of algebras,
, that is a quantization of the function algebra
on the coadjoint representation. Along the parameter t the family gives a quantization of the Lie bracket. This family induces a two parametric
-invariant quantization on the maximal orbits, which includes a quantization of the Kirillov-Kostant-Souriau bracket. Yet we construct a quantum de Rham complex on
. 相似文献
6.
Tomoyuki Arakawa Tomoki Nakanishi Kazuyuki Oshima Akihiro Tsuchiya 《Communications in Mathematical Physics》1996,181(1):157-182
We give thespectral decomposition of the path space of the
vertex model with respect to the local energy functions. The result suggests the hidden Yangian module structure on the
levell integrable modules, which is consistent with the earlier work [1] in the level one case. Also we prove the fermionic character formula of the
levell integrable representations in consequence. 相似文献
7.
We study analogues of the Yangian of the Lie algebra
for the other classical Lie algebras
and
. We call them twisted Yangians. They are coideal subalgebras in the Yangian of
and admit homomorphisms onto the universal enveloping algebras U(
) and U(
) respectively. In every twisted Yangian we construct a family of maximal commutative subalgebras parametrized by the regular semisimple elements of the corresponding classical Lie algebra. The images in U(
) and U(
) of these subalgebras are also maximal commutative. 相似文献
8.
D. Arnaudon 《Czechoslovak Journal of Physics》1997,47(11):1075-1082
Irreducible representations of
at roots of unity in the restricted specialisation are described with the Gelfand-Zetlin basis. This basis is redefined to allow the Casimir operator of the quantum subalgebra
not to be completely diagonalised. Some irreducible representations of
indeed contain indecomposable
-modules. The set of redefined (mixed) states is described as a teepee inside the pyramid made with the whole representation. 相似文献
9.
A. A. Raduta 《Czechoslovak Journal of Physics》2000,50(4):519-527
Two neutrino double beta (2) Gamow-Teller transitions,
and
, are treated with a many-body Hamiltonian involving a Bonn-type realistic two-body interaction. The states involved in these transitions are described by a pnRQRPA approach. Transition operators are expanded in first order in terms of renormalized bosons. For illustration the formalism is applied to the case
Kr. 相似文献
10.
We classify the finite-dimensional irreducible representations of the quantum affine algebra
in terms of highest weights (this result has a straightforward generalization for arbitrary quantum affine algebras). We also give an explicit construction of all such representations by means of an evaluation homomorphism
, first introduced by M. Jimbo. This is used to compute the trigonometricR-matrices associated to finite-dimensional representations of
. 相似文献
11.
We show that the action of the universalR-matrix of the affine
quantum algebra, whenq is a root of unity, can be renormalized by some scalar factor to give a well-defined nonsingular expression, satisfying the Yang-Baxter equation. It can be reduced to intertwining operators of representations, corresponding to Chiral Potts, if the parameters of these representations lie on the well-known algebraic curve.We also show that the affine
forq is a root of unity from the autoquasitriangular Hopf algebra in the sense of Reshetikhin.This work is supported by NATO linkage grant LG 9303057. 相似文献
12.
S. L. Woronowicz 《Communications in Mathematical Physics》1972,28(3):221-235
Let
be aC*-algebra and
be an opposite algebra. Notions of exact andj-positive states of
are introduced. It is shown, that any factor state of
can be extended to a pure exactj-positive state
of
. The correspondence
generalizes the notion of the purifications map introduced by Powers and Størmer. The factor states 1 and 2 are quasi-equivalent if and only if their purifications
and
are equivalent. 相似文献
13.
We show that the Ashtekar-Isham extension
of the configuration space of Yang-Mills theories
is (topologically and measure-theoretically) the projective limit of a family of finite dimensional spaces associated with arbitrary finite lattices.These results are then used to prove that
is contained in a zero measure subset of
with respect to the diffeomorphism invariant Ashtekar-Lewandowski measure on
. Much as in scalar field theory, this implies that states in the quantum theory associated with this measure can be realized as functions on the extended configuration space
. 相似文献
14.
Sergio Doplicher Daniel Kastler Derek W. Robinson 《Communications in Mathematical Physics》1966,3(1):1-28
Starting from aC*-algebra
and a locally compact groupT of automorphisms of
we construct a covariance algebra
with the property that the corresponding *-representations are in one-to-one correspondence with covariant representations of
i.e. *-representations of
in which the automorphisms are continuously unitarily implemented. We further construct for relativistic field theory an algebra
yielding the *-representations of
in which the space time translations have their spectrum contained inV. The problem of denumerable occurence of superselection sectors is formulated as a condition on the spectrum of
. Finally we consider the covariance algebra
built with space translations alone and show its relevance for the discussion of equilibrium states in statistical mechanics, namely we restore in this framework the equivalence of uniqueness of the vacuum, irreducibility and a weak clustering property.On leave of absence from Istituto di Fisica G. Marconi — Roma. 相似文献
15.
We present an analysis of nonannihilation channels in four-pronged
interactions at 5·68 GeV/c. The transverse momenta and azimuthal angles distributions of nucléons and -mesons are compared with phase space. No essential influence of
production on azimuthal correlation has been found. The seen difference of azimuthal angle distributions for like and unlike charged pions in annihilations appears to be more pronounced for small transverse momenta and for small transverse masses. For 10971 events of the reaction ¯pp¯pp–+ we present cross sections for
production and differential cross sections. The reaction is dominated by the strong quasi-two-body channel
with cross section (1·66 ±±0·10) mb. We study in detail the production mechanism of this channel in terms of the absorption model.Dedicated to Academician Václav Votruba on the occasion of his seventieth birthday.The authors are indebted to the CERN-Prague collaboration on ¯pp interactions at 5·7 GeV/c for experimental data used in this paper and to Dr. M. Novak for valuable comments. 相似文献
16.
Neutrinoless double-beta decay within Minimal Supersymmetric Standard Model with gauge mediated supersymmetry breaking is considered. Limits on R-parity breaking constant
coming from non-observability of 0 in 76Ge are found. The dependence of
on different parameters at the messenger scale M are shown, with special attention paid to nuclear part of calculations. We have found that
strongly depends on the effective supersymmetry breaking scale only and deduced limits imposed on this non-standard parameter by the germanium experiment. 相似文献
17.
We use the recursion method to calculate the vibrational density of states
of site percolation clusters slightly above the percolation threshold. It is found that
is proportional to at long wavelengths. At shorter length scales,
is proportional to
, with the fraction dimension
. The cross-over from phonon to fraction regime is characterized by a rapid rise in
in agreement with effective medium calculations. 相似文献
18.
Giving an ultraviolet regularization and volume cut off we construct a nuclear Riemannian structure on the Hilbert manifold
of gauge orbits. This permits us to define a regularized Laplace-Beltrami operator on
and an associated global diffusion in
governed by . This enables us to define, via a Feynman-Kac integral, a Euclidean, continuum regularized Yang-Mills process corresponding to a suitable regularization (of the kinetic term) of the classical Yang-Mills Lagrangian onT
.On leave of absence from Zaragoza University (Spain)Laboratoire associé au CNRS 相似文献
19.
Jouko Mickelsson 《Letters in Mathematical Physics》1991,22(2):131-139
An extension
of the symmetry group GL of Sato's universal Grassmannian GM is constructed. The extension plays a similar role to that of the central extension
in the approach of Segal and Wilson to functions and KP hierarchy. Our group G contains GLres as a subgroup and the associated function is a deformation of the usual function, leading to a deformed KP hierarchy. A relation to current algebra of Yang-Mills theory in 3+1 dimension is discussed. 相似文献
20.
Total electron emission from metals due to the impact of multiply charged ions, , may significantly influence quantitative measurements of ion current in corpuscular diagnostics. The value of (/q) was determined for Xe ions impacting clean polycrystalline copper as a function of ion charge state
and of ion kinetic energy,
keV/q, i.e. in the energy region up to
keV/amu, where there is a lack of such data. For highly charged projectile ions,
was found to have a clear minimum as a function of E
i. With decreasing charge state of the projectile ion this minimum shifts to a lower energy and becomes shallower. This observation is in agreement with compiled results of other authors. Limits for values of
are estimated and discussed. 相似文献