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1.
Jie Miao 《Integral Equations and Operator Theory》2007,59(1):53-65
We give a necessary and sufficient condition for Hankel operators Hf on the harmonic Bergman space of the unit ball to be in the Schatten p-class for 2 ≤ p < ∞. A special case when symbol f is a harmonic function is also considered. 相似文献
2.
3.
The nontangential behavior of the Bergman metric near a smooth convex boundary point of a bounded pseudoconvex domain D
n
is studied in terms of its multitype.Received January 25, 2002; in revised form June 20, 2002
Published online November 18, 2002 相似文献
4.
T. Rivoal 《Monatshefte für Mathematik》2007,150(1):49-71
Diophantine Properties of Lehmer’s Continued Cotangent Developments. This article deals with an algorithm devised by Lehmer which enables us to write any real positive number as the sum of an
alternating series of cotangents of integers n
ν, ν ≥ 0, in a unique way. We continue the work begun by Lehmer and continued by Shallit: amongst other things, we give explicitly
the link between the rational approximations of a given real number coming from this algorithm and the usual convergents of
the same real number and we produce a quasi-optimal bound for the growth of the sequence (n
ν)ν ≥ 0 associated to an algebraic number. We also determine the regular continued fractions of an exceptional class of continued
cotangent developments, which enables us to produce optimal irrationality measures of these expansions. 相似文献
5.
Elói Medina Galego 《Monatshefte für Mathematik》2002,136(2):87-97
We study the relation of to the subspaces and quotients of Banach spaces of continuous vector-valued functions , where K is an arbitrary dispersed compact set. More precisely, we prove that every infinite dimensional closed subspace of totally incomparable to X contains a copy of complemented in . This is a natural continuation of results of Cembranos-Freniche and Lotz-Peck-Porta. We also improve our result when K is homeomorphic to an interval of ordinals. Next we show that complemented subspaces (resp., quotients) of which contain no copy of are isomorphic to complemented subspaces (resp., quotients) of some finite sum of X. As a consequence, we prove that every infinite dimensional quotient of which is quotient incomparable to X, contains a complemented copy of . Finally we present some more geometric properties of spaces.
Received 8 November 2000; in revised form 7 December 2001 相似文献
6.
Orthogonal decompositions of Sobolev spaces in Clifford analysis 总被引:2,自引:0,他引:2
The space L
2(G;ℂ
m
) of Clifford-algebra-valued functions in bounded domains G of ℝ
m
is decomposed into the orthogonal sum of the subspace of poly-left-monogenic functions of arbitrary order k≥1 and its orthogonal complement and as well into the orthogonal sum of the subspace of polyharmonic functions of arbitrary
order k≥1 and its orthogonal complement. The complementary subspaces are given explicitly. In the particular case m=2, complex functions are involved. Although this case has to be treated separately, the results are as before. The proofs
are based on proper higher-order Cauchy–Pompeiu formulas and Green functions for powers of the Laplacian.
Received: July 4, 2000; in final form: January 7, 2001?Published online: December 19, 2001 相似文献
7.
Jorge J. Betancor Claudio Jerez Sandra M. Molina Lourdes Rodríguez-Mesa 《Monatshefte für Mathematik》2008,153(2):89-103
In this paper we study the Hankel transformation and convolution on certain spaces
of entire functions and its dual
that is a space of hyperfunctions and contains the (even)-Schwartz space S
e
′. We prove that the Hankel transform is an automorphism of
. Also the Hankel convolutors of
are investigated.
Authors’ addresses: Jorge J. Betancor, Claudio Jerez and Lourdes Rodríguez-Mesa, Departamento de Análisis Matemático, Universidad
de la Laguna, Campus de Anchieta, Avda. Astrofísico Francisco Sánchez, s/n, 38271 La Laguna (Sta. Cruz de Tenerife), Espa?a;
Sandra M. Molina, Departamento de Matemáticas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata,
Funes 3350 (7600), Mar del Plata, Argentina 相似文献
8.
9.
Ernst Albrecht 《Archiv der Mathematik》2009,92(5):399-404
The problem of uniqueness of the Chebyshev polynomials for bounded linear operators on normed linear spaces is investigated.
Herrn Professor Dr. Dr. h.c. Heinz K?nig zu seinem achtzigsten Geburtstag gewidmet 相似文献
10.
Multiplication operators in weighted Banach (and locally convex) spaces of functions holomorphic in the unit disc are well
known. In this note we investigate the connection between power boundedness, mean ergodicity and uniform mean ergodicity of
such operators.
Received: 13 October 2008, Revised: 18 November 2008 相似文献
11.
We will prove a result concerning the inclusion of non-trivial invariant ideals inside non-trivial ideals of a twisted crossed
product. We will also give results concerning the primeness and simplicity of crossed products of twisted actions of locally
compact groups on -algebras.
Received: 25 January 2002; in final form: 22 May 2002/Published online: 2 December 2002
This work is partially supported by Hong Kong RGC Direct Grant. 相似文献
12.
A multilinear version of the Boyd interpolation theorem is proved in the context of quasi-normed rearrangement-invariant
spaces. A multilinear Marcinkiewicz interpolation theorem is obtained as a corollary. Several applications are given, including
estimates for bilinear fractional integrals.
Received January 31, 1999 / Accepted February 27, 2000 / Published online December 8, 2000 相似文献
13.
Antonio M. Peralta 《manuscripta mathematica》2001,105(2):265-281
In this paper we introduce 2-JB*-triple-summing operators on real and complex JB*-triples. These operators generalize 2-C*-summing operators on C*-algebras. We also obtain a Pietsch's factorization theorem in the setting of 2-JB*-triple-summing operators on JB*-triples.
Received: 18 December 2000 相似文献
14.
Optimal in a certain sense sufficient conditions are given for the existence and uniqueness of ω-periodic solutions of the
nonautonomous ordinary differential equation u
(2m)
=f(t,u,...,u
(m-1)
), where the function f:ℝ×ℝ
m
→ℝ is periodic with respect to the first argument with period ω.
Received: December 21, 1999; in final form: August 12, 2000?Published online: October 2, 2001 相似文献
15.
Benoit Florent Sehba 《Integral Equations and Operator Theory》2008,62(2):233-245
We present here some criteria for Schatten-Von Neumann class membership for the small Hankel operator on Bergman space A
2(T
Ω), when T
Ω is the tube over the symmetric cone Ω.
The author would like to thank professor Aline Bonami for helpful advices. 相似文献
16.
We prove that in a Banach space admitting a separating polynomial, each weakly null normalized sequence has a subsequence
which is equivalent to the usual basis of some , p an even integer. We show that for each even integer p, the Schatten class admits a separating polynomial. For a space with a basis admitting a 4-homogeneous separating polynomial, we relate the unconditionality
of the basis with the existence of certain type of polynomials defined in terms of infinite symmetric matrices. We find relations
between the properties of the entries of these matrices and the geometrical structure of the space. Finally we study the existence
of convex 4-homogeneous separating polynomials.
Received 3 January 2001 相似文献
17.
18.
In this paper we study the Cauchy problem for overdetermined systems of linear partial differential operators with constant
coefficients in some spaces of ultradifferentiable functions of class (M
p
). We show that evolution is equivalent to the validity of a Phragmén-Lindel?f principle for entire and plurisubharmonic functions
on some irreducible affine algebraic varieties, and make applications in different situations. We find necessary and sufficient
conditions for well posedness, and relate the hyperbolicity of a given system to that of its principal part.
Received: January 19, 1999?Published online: May 10, 2001 相似文献
19.
We prove that a domain in whose quasihyperbolic metric satisfies a logarithmic growth condition with coefficient is a (q,p)-\Poincare domain for all p and q satisfying and , where denotes the Sobolev conjugate exponent. An elementary example shows that the given ranges for p and q are sharp. The proof makes use of estimates for a variational capacity. When p=2 we give an application to the solvability of the Neumann problem on domains with irregular boundaries. We also discuss
the relationship between this growth condition on the quasihyperbolic metric and the s-John condition.
Received: 2 May 2000 / Published online: 17 June 2002 相似文献
20.
Gilles Godefroy 《Archiv der Mathematik》2009,92(5):476-484
Our main result shows that subspaces of L1([0, 1]) on which the blow-up operators act compactly are isometric to dual spaces, and their natural predual belongs to the
Banach-Mazur closure of quotient spaces of . Related general results are shown for subspaces X of or of reflexive K?the function spaces, which imply that when X consists of smooth functions it embeds into a Banach space with an unconditional basis.
Received: 25 September 2008 相似文献