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911.
We show that the coset
is a quantum Hamiltonian reduction of the exceptional affine Lie superalgebra
and that the corresponding W algebra is the commutant of the
quantum group. 相似文献
912.
We obtain the normally ordered form of the general multimode exponential operator by means of parameter differentiation method and its antinormally ordered form by virtue of the technique of integration within an ordered product of operators.As an application,we obtain a new comp[leteness relation in n-mode Fock space. 相似文献
913.
914.
We define a 4-parameter family of generically irreducible and inequivalent representations of the Witt Lie algebra on which the infinitesimal rotation operator acts semisimply with infinite-dimensional eigenspaces. They are deformations of the (generically indecomposable) representations on spaces of polynomial differential operators between two spaces of tensor densities on S
1, which are constructed by composing each such differential operator with the action of a rotation by a fixed angle. 相似文献
915.
Given a variety , we provide an axiomatization of the class of complex algebras of algebras in . can be obtained effectively from the axiomatization of ; in fact, if this axiomatization is recursively enumerable, then is recursive.
Received January 18, 2000; accepted in final form December 18, 2000. 相似文献
916.
Let S be the multiplication operator by an independent variable x in L
2(0,1), and let V be an integral operator of Volterra type. In this note, we find sufficient conditions for the similarity of the operators T := S + V and S and discuss some generalizations to an abstract setting of the results obtained. 相似文献
917.
三维各向同性谐振子的超对称量子力学体系 总被引:3,自引:3,他引:0
利用三维各向同性谐振子的中升、降算子,分别构造不同的超对称量子力学体系,并研究了它们的性质。 相似文献
918.
The Fredholm determinant asymptotics for self-adjoint convolution operators on finite intervals with real symbols vanishing on the real axis is studied. Explicit formulae are obtained in the case where the symbol satisfies the generalized zero index condition and has only two simple zeros of analytic type. These formulae are direct extensions of the Ahiezer–Kac–Szegö limit theorem which, in particular, take into account the oscillating character of the asymptotics. 相似文献
919.
This paper deals with the spectral problems for high-order nonsymmetric difference operators. The method of investigation
is based on the analysis of the genetic sums formulas for the moments of the operator. The parameters of these sums are shown
to be connected with coefficients of the introduced vector Stieltjes continued fraction. The connections with vector orthogonality,
Hermite—Padé approximation, and Hankel determinants are investigated. This gives a tool for the analysis of the solution of
the direct and inverse spectral problem of the operator. It is applied to the integration of hierarchy of the discrete KdV
equations. The existence of a global solution is proved.
July 13, 1998. Date revised: July 12, 1999. Date accepted: July 26, 1999. 相似文献
920.
Liliana GRATIE 《数学年刊B辑(英文版)》2000,21(2):147-152
gi.TheTOpologicalDegreeforGeneralizedMonotoneOperatorsMonotoneoperatortheoryisoftenanefficienttoolforprovingtheexistenceofsolutionstononlinearProblems.Inparticular,thepseudo-monotoneoperatorsintroducedbyBrezis[2]areveryusefulforstudyingnonlinearellipticproblems.Weconsiderherethefollowingclassesofmappingsofgeneralizedmonotonetype.(QM)=theclassofquasi-mollotoneoperators,(S )=theclassofoperatorsoftype(S ),(PM)=theclassofpseudthmonotoneoperators,(LS)=theclassofLeray-Schauderoperators(compac… 相似文献