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991.
We define permutation modules and Young modules for the Brauer algebra B
k
(r,δ), and show that if the characteristic of the field k is neither 2 nor 3 then every permutation module is a sum of Young modules, respecting an ordering condition similar to that
for symmetric groups. Moreover, we determine precisely in which cases cell module filtration multiplicities are well-defined,
as done by Hemmer and Nakano for symmetric groups.
Supported by the European Community through Marie Curie fellowship MCFI 2002-01325
Supported by EPSRC grant GR/S18151/01 相似文献
992.
993.
994.
Dagmar Medková 《Integral Equations and Operator Theory》2006,54(2):235-258
The third problem for the Laplace equation is studied on an open set with Lipschitz boundary. The boundary condition is in
Lp and it is fulfilled in the sense of the nontangential limit. The existence and the uniqueness of a solution is proved and
the solution is expressed in the form of a single layer potential. For domains with C1 boundary the explicit solution of the problem is calculated. 相似文献
995.
Adam W. Marczak 《Algebra Universalis》2006,55(1):57-66
In this paper we prove that if a groupoid has exactly
distinct n-ary term operations for n=1, 2, 3 and the same number of constant unary term operations for n=0, then it is a normalization of a nontrivial Boolean algebra. This, together with some general facts concerning normalizations
of algebras, which we recall, yields a clone characterization of normalizations of nontrivial Boolean algebras: A groupoid
(G;·) is clone equivalent to a normalization of a nontrivial Boolean algebra if and only if the value of the free spectrum for
(G;·) is
for n = 0, 1, 2, 3. In the last section the Minimal Extension Property for the sequence (2, 3) in the class of all groupoids is
derived.
Received September 15, 2004; accepted in final form October 4, 2005. 相似文献
996.
Existence of Positive Solutions for Operator Equations and Applications to Semipositone Problems 总被引:2,自引:0,他引:2
In this paper we study the existence of positive solutions of the following operator equation in a Banach space E:
where G(x, λ) = λKFx+e0, K: E↦ E is a linear completely continuous operator, F: P↦ E is a nonlinear continuous , bounded operator, e0∈ E, λ is
a parameter and P is a cone of Banach space E. Since F is not assumed to be positive and e0 may be a negative element, the operator equation is a so-called semipositone problem. We prove that under certain super-linear
conditions on the operator F the operator equation has at least one positive solution for λ > 0 sufficiently small, and that under certain sub-linear
conditions on the operator F the operator equation has at least one positive solution for λ > 0 sufficiently large. In addition, we briefly outline an application of our results which simplify previous theorems in
the literature. 相似文献
997.
José G. Llavona 《Mediterranean Journal of Mathematics》2006,3(2):259-271
This paper is a survey of approximation results and methods by smooth functions in Banach spaces. The topics considered in
the paper are the following: approximation by polynomials by Ck-functions using the method of smooth partitions of unity, approximation by the fine topology, analytic approximation and
regularization in Banach spaces using the infimal convolution method. 相似文献
998.
Alexander Brudnyi 《Journal of Functional Analysis》2006,231(2):418-437
The classical integral representation formulas for holomorphic functions defined on pseudoconvex domains in Stein manifolds play an important role in the constructive theory of functions of several complex variables. In this paper, we will show how to construct similar formulas for certain classes of holomorphic functions defined on coverings of such domains. 相似文献
999.
On the concepts of intertwining operator and tensor product module in vertex operator algebra theory
Yi-Zhi Huang James Lepowsky Haisheng Li Lin Zhang 《Journal of Pure and Applied Algebra》2006,204(3):507-535
We produce counterexamples to show that in the definition of the notion of intertwining operator for modules for a vertex operator algebra, the commutator formula cannot in general be used as a replacement axiom for the Jacobi identity. We further give a sufficient condition for the commutator formula to imply the Jacobi identity in this definition. Using these results we illuminate the crucial role of the condition called the “compatibility condition” in the construction of the tensor product module in vertex operator algebra theory, as carried out in work of Huang and Lepowsky. In particular, we prove by means of suitable counterexamples that the compatibility condition was indeed needed in this theory. 相似文献
1000.
M. Sioen 《Journal of Pure and Applied Algebra》2006,207(3):675
In this work we investigate the natural algebraic structure that arises on dual spaces in the context of quantified functional analysis. We show that the category of absolutely convex modules is obtained as the category of Eilenberg-Moore algebras induced by the dualization functor [−,R] on locally convex approach spaces. We also establish a dual adjunction between the latter category and the category of seminormed spaces. 相似文献