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861.
862.
863.
In this paper we present an inertia result for Stein equations with
an indefinite right hand side. This result is applied to establish connnections
between the inertia of invertible hermitian block Toeplitz matrices and associated
orthogonal polynomials. 相似文献
864.
J.?Ramírez?OrtegaEmail author N.?L.?Vasilevski E.?Ramírez?de?Arellano 《Integral Equations and Operator Theory》2003,46(4):455-471
Let be a domain with smooth boundary and let α be a C
2-
diffeomorphism on satisfying the Carleman condition .We denote
by the C*-algebra generated by the Bergman projection of G, all multiplication
operators aI and the operator where is the Jacobian of α. A symbol algebra of is determined and Fredholm
conditions are given. We prove that the C*-algebra generated by the Bergman
projection of the upper half-plane and the operator is isomorphic
and isometric to .
Submitted: February 11, 2001?Revised: January 27, 2002 相似文献
865.
We introduce a class of function algebras, that we call unimodular,
and study Toeplitz operators on the Hardy spaces associated to representing
measures on these algebras.We show that our class of function algebras is very
extensive and that a number of important results for Toeplitz operators and
their associated C*-algebras extend to the very general setting we consider.
Submitted: July 1. 2001. 相似文献
866.
Given an admissible measure μ on where is an open set, we define a realization of the Laplacian in with general Robin boundary conditions and we show that generates a holomorphic C
0
-semigroup on which is sandwiched by the Dirichlet Laplacian and the Neumann Laplacian semigroups. Moreover, under a locality and a regularity
assumption, the generator of each sandwiched semigroup is of the form . We also show that if contains smooth functions, then μ is of the form (where σ is the (n-1)-dimensional Hausdorff measure and β a positive measurable bounded function on ); i.e. we have the classical Robin boundary conditions.
RID="h1"
ID="h1"Dédié à Philippe Bénilan
RID="*"
ID="h1"This work is part of the DGF-Project: "Regularit?t und Asymptotik für elliptische und parabolische Probleme". 相似文献
867.
In this paper we show that the parabolic problem associated with elliptic operators A having coefficients in has the property of maximal -regularity.
RID="h1"
ID="h1"In Memoriam Philippe Bénilan 相似文献
868.
869.
We consider the problem of characterizing some minimal submanifolds using the spectrum0Spec of the Laplace-Beltrami operator acting on fucntions. In particular we characterize then-dimensional compact minimal totally real parallel submanifolds immersed in the complex projective spaceCP
n, 3≤n≤6, by their0Spec in the class of all compact totally real minimal submanifolds ofCP
n. Moreover, we characterize the Clifford torus
by its0Spec in the class of all compact minimal submanifolds of the Euclidean sphereS
n+1(1).
Authors supported by funds of the University of Lecce and the M.U.R.S.T. 相似文献
870.
It is well known that the recurrence relations
are periodic, in the sense that they define periodic sequences for all choices of the initial data, and lead to sequences
with periods 2, 5 and 8, respectively. In this paper we determine all periodic recursions of the form
where are complex numbers, are non-zero and . We find that, apart from the three recursions listed above, only
lead to periodic sequences (with periods 6 and 8). The non-periodicity of (R) when (or and ) depends on the connection between (R) and the recurrence relations
and
We investigate these recursions together with the related
Each of (A), (B), and (C) leads to periodic sequences if k = 1 (with periods 6, 5, and 9, respectively). Also, for k = 2, (B) leads to periodicity with period 8. However, no other cases give rise to periodicity. We also prove that every real
sequence satisfying any of (A), (B), and (C) must be bounded. As a consequence, we find that for an arbitrary k, every rational sequence satisfying any of (A), (B), and (C) must be periodic.
(Received 27 June 2000; in revised form 5 January 2001) 相似文献