共查询到20条相似文献,搜索用时 15 毫秒
1.
S Poornima 《Journal of Functional Analysis》1982,45(1):1-28
Let Wm,p denote the Sobolev space of functions on n whose distributional derivatives of order up to m lie in Lp(n) for 1 ? p ? ∞. When 1 < p < ∞, it is known that the multipliers on Wm,p are the same as those on Lp. This result is true for p = 1 only if n = 1. For, we prove that the integrable distributions of order ?1 whose first order derivatives are also integrable of order ?1, belong to the class of multipliers on Wm,1 and there are such distributions which are not bounded measures. These distributions are also multipliers on Lp, for 1 < p < ∞. Moreover, they form exactly the multiplier space of a certain Segal algebra. We have also proved that the multipliers on Wm,l are necessarily integrable distributions of order ?1 or ?2 accordingly as m is odd or even. We have obtained the multipliers from L1(n) into Wm,p, 1 ? p ? ∞, and the multiplier space of Wm,1 is realised as a dual space of certain continuous functions on n which vanish at infinity. 相似文献
2.
A. B. Gulisashvili 《Journal of Mathematical Sciences》1985,31(1):2662-2672
It is proved in this paper that the characteristic function of the half-space is not a multiplier for the pair (B
pq
1/p
, B
p
1/p
), 1<p<, 1<q . In addition, necessary and sufficient conditions are found for the validity of the inclusion.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 135, pp. 36–50, 1984. 相似文献
3.
4.
Multipliers and Herz type spaces 总被引:1,自引:0,他引:1
ShanZhen Lu 《中国科学A辑(英文版)》2008,51(10):1919-1936
Hrmander condition for boundedness of multiplier operators will be replaced by a weaker condition described by certain weighted or non-weighted Herz spaces. Some results on boundedness of multiplier operators are then established. As direct corollaries of main theorems in this paper, several celebrated results on boundedness of multiplier operators will be improved or deduced. 相似文献
5.
Multipliers between Dirichlet spaces 总被引:1,自引:0,他引:1
6.
Dashan Fan 《Rendiconti del Circolo Matematico di Palermo》1994,43(3):449-463
Si generalizza un teorema di deLeeuw per moltiplicatiri su spazi di Lorentz e spazi con norme miste.
Dedicated to my dear teacher, Professor Guido Weiss, for his 65 birthday 相似文献
Dedicated to my dear teacher, Professor Guido Weiss, for his 65 birthday 相似文献
7.
Xavier Dussau 《Proceedings of the American Mathematical Society》2005,133(5):1379-1386
We prove for some translation-invariant weighted spaces the following characterization: is a multiplier of if and only if leaves invariant every translation-invariant subspace of . This result is equivalent with the reflexivity of the multiplier algebra of .
8.
O. V. Ivanov 《Siberian Mathematical Journal》1991,32(1):28-32
Donetsk. Translated from Sibirskii Matematicheskii Zhurnal, Vol. 32, No. 1, pp. 37–42, January–February, 1991. 相似文献
9.
The results of this paper have been presented by the second author at the joint AMS-DMV Meeting 1993 in Heidelberg (Germany) 相似文献
10.
We show that a usual corona-type theorem on a space of functions automatically extends to a matrix version.
11.
Oscillatory Riemann-Hilbert problems and the corona theorem 总被引:1,自引:0,他引:1
M.A. Bastos 《Journal of Functional Analysis》2003,197(2):347-397
The paper is devoted to the Riemann-Hilbert problem with matrix coefficient having in Hardy spaces [Hp±]2,1<p?∞, on half-planes . Under the assumption of existence of a non-trivial solution of corresponding homogeneous Riemann-Hilbert problem in [H∞±]2 we study the solvability of the non-homogeneous Riemann-Hilbert problem in [Hp±]2,1<p<∞, and get criteria for the existence of a generalized canonical factorization and bounded canonical factorization for G as well as explicit formulas for its factors in terms of solutions of two associated corona problems (in and ). A separation principle for constructing corona solutions from simpler ones is developed and corona solutions for a number of corona problems in H∞+ are obtained. Making use of these results we construct explicitly canonical factorizations for triangular bounded measurable or almost periodic 2×2 matrix functions whose diagonal entries do not possess factorizations. Such matrices arise, e.g., in the theory of convolution type equations on finite intervals. 相似文献
12.
A self-contained account of the theory of sub-Stonean spaces, and their relations to Stonean spaces and Rickart spaces is given. Of particular interest are the corona sets (of the form β(X) for locally compact, σ-compact spaces, because these highly nontrivial sub-Stonean spaces lend themselves to C?ech-cohomological considerations. The theory of sub-Stonean spaces is essential for our solution of the diagonalization problem for C(X)? Mn, found in K. Grove and G. K. Pedersen, Diagonalizing matrices over C(X), submitted for publication. 相似文献
13.
P.G. Lemarié-Rieusset S. Gala 《Journal of Mathematical Analysis and Applications》2006,322(2):1030-1054
We characterize the pointwise multipliers which maps a Sobolev space to a Sobolev space in the case |s|<r<d/2. 相似文献
14.
15.
Nikola Pandeski 《Mathematische Annalen》1990,287(1):185-192
16.
We extend the ``matricial corona theorem' of M. Andersson to general algebras of functions which satisfy a corona theorem.
17.
Sadek Gala 《Journal of Mathematical Analysis and Applications》2006,324(2):1262-1273
Let σ(x,ξ) be a sufficiently regular function defined on Rd×Rd. The pseudo-differential operator with symbol σ is defined on the Schwartz class by the formula
18.
Bert Wiest 《Proceedings of the American Mathematical Society》2000,128(12):3741-3747
For a smooth, finite-dimensional manifold with a submanifold we study the topology of the straight loop space , the space of loops whose intersections with are subject to a certain transversality condition. Our main tool is Rourke and Sanderson's compression theorem. We prove that the homotopy type of the straight loop space of a link in depends only on the number of link components.
19.
We study the L
p
-boundedness of spectral multipliers on non-compact locally symmetric spaces of rank one. 相似文献