- Research
- Open access
- Published:
Sharp maximal function inequalities and boundedness for commutators related to generalized fractional singular integral operators
Journal of Inequalities and Applications volume 2014, Article number: 211 (2014)
Abstract
In this paper, some sharp maximal function inequalities for the commutators related to certain generalized fractional singular integral operators are proved. As an application, we obtain the boundedness of the commutators on Lebesgue, Morrey and Triebel-Lizorkin spaces.
MSC:42B20, 42B25.
1 Introduction and preliminaries
Let and T be the Calderón-Zygmund singular integral operator. The commutator generated by b and T is defined by
By using a classical result of Coifman et al. (see [1]), we know that the commutator is bounded on (). Now, as the development of singular integral operators and their commutators, some new integral operators and their commutators are studied (see [2–7]). In [5, 8, 9], the boundedness for the commutators generated by the singular integral operators and Lipschitz functions on Triebel-Lizorkin and () spaces are obtained. In [10], some singular integral operators with general kernel are introduced, and the boundedness for the operators and their commutators generated by and Lipschitz functions are obtained (see [10, 11]). Motivated by these, in this paper, we will prove some sharp maximal function inequalities for the commutator associated with certain generalized fractional singular integral operators and the and Lipschitz functions. As an application, we obtain the boundedness of the commutator on Lebesgue, Morrey and Triebel-Lizorkin space.
First, let us introduce some preliminaries. Throughout this paper, Q will denote a cube of with sides parallel to the axes. For any locally integrable function f, the sharp maximal function of f is defined by
and here, and in what follows, . It is well known that (see [12, 13])
We say that f belongs to if belongs to and define . It is well known that (see [7])
Let
For , let .
For and , set
The weight is defined by (see [12])
and
For and , let be the homogeneous Triebel-Lizorkin space (see [9]).
For , the Lipschitz space is the space of functions f such that
In this paper, we will study some singular integral operators as follows (see [10]).
Definition 1 Fix . Let be a linear operator such that is bounded on and has a kernel K, that is, there exists a locally integrable function on such that
for every bounded and compactly supported function f, where for K we have the following: there is a sequence of positive constant numbers such that for any ,
and
where and . We write .
Let b be a locally integrable function on . The commutator related to is defined by
Remark (a) Note that the classical Calderón-Zygmund singular integral operator satisfies Definition 1 with , and (see [12, 13]).
-
(b)
Also note that the fractional integral operator with rough kernel satisfies Definition 1 (see [2]), that is, for , let be the fractional integral operator with rough kernel defined by (see [2])
where Ω is homogeneous of degree zero on , and for some , that is, there exists a constant such that for any , . When , is the Riesz potential (fractional integral operator).
Definition 2 Let φ be a positive, increasing function on and there exists a constant such that
Let f be a locally integrable function on . Set, for and ,
where . The generalized fractional Morrey space is defined by
We write if , which is the generalized Morrey space. If , , then , which is the classical Morrey spaces (see [7, 14]). If , then , which is the Lebesgue spaces.
As the Morrey space may be considered as an extension of the Lebesgue space, it is natural and important to study the boundedness of operator on Morrey spaces (see [3, 4, 6, 15, 16]).
It is well known that commutators are of great interest in harmonic analysis, and they have been widely studied by many authors (see [2, 7]). In [7], Pérez and Trujillo-Gonzalez prove a sharp estimate for the commutator. The main purpose of this paper is to prove some sharp maximal inequalities for the commutator . As an application, we obtain the -norm inequality, and for Morrey and Triebel-Lizorkin spaces boundedness for the commutator.
2 Theorems
We shall prove the following theorems.
Theorem 1 Let there be a sequence , , and . Suppose is a bounded linear operator from to for any p, r with and , and that it has a kernel K satisfying (1). Then there exists a constant such that, for any and ,
Theorem 2 Let there be a sequence , , and . Suppose is a bounded linear operator from to for any p, r with and , and that it has a kernel K satisfying (1). Then there exists a constant such that, for any and ,
Theorem 3 Let there be a sequence , and . Suppose is a bounded linear operator from to for any p, r with and , and that it has a kernel K satisfying (1). Then there exists a constant such that, for any and ,
Theorem 4 Let there be a sequence , , , and . Suppose is a bounded linear operator from to and has a kernel K satisfying (1). Then is bounded from to .
Theorem 5 Let there be a sequence , , , , and . Suppose is a bounded linear operator from to and has a kernel K satisfying (1). Then is bounded from to .
Theorem 6 Let there be a sequence , , , and . Suppose is a bounded linear operator from to and has a kernel K satisfying (1). Then is bounded from to .
Theorem 7 Let there be a sequence , , and . Suppose is a bounded linear operator from to and has a kernel K satisfying (1). Then is bounded from to .
Theorem 8 Let there be a sequence , , , and . Suppose is a bounded linear operator from to and has a kernel K satisfying (1). Then is bounded from to .
Corollary Let , that is, is the singular integral operator as Definition 1. Then Theorems 1-8 hold for .
3 Proofs of theorems
To prove the theorems, we need the following lemma.
Lemma 1 (see [10])
Let be the singular integral operator as Definition 1. Then is bounded from to for and .
Lemma 2 (see [17])
For and , we have
Lemma 3 (see [4])
Let and . Then, for any smooth function f for which the left-hand side is finite,
Suppose that , and . Then
Lemma 5 Let , . Then, for any smooth function f for which the left-hand side is finite,
Proof For any cube in , we know for any cube by [18]. Noticing that and if , by Lemma 3, we have, for ,
thus
and
This finishes the proof. □
Lemma 6 Let be a bounded linear operator from to for any p, r with and , . Then
Lemma 7 Let , and . Then
The proofs of two Lemmas are similar to that of Lemma 5 by Lemmas 1 and 4, we omit the details.
Proof of Theorem 1 It suffices to prove for and some constant that the following inequality holds:
Fix a cube and . Write, for and ,
Then
For , by Hölder’s inequality, we obtain
For , choose such that , by -boundedness of , we get
For , recalling that , we have
These complete the proof of Theorem 1. □
Proof of Theorem 2 It suffices to prove for and some constant that the following inequality holds:
Fix a cube and . Write, for and ,
Then
By using the same argument as in the proof of Theorem 1, we get, for with ,
This completes the proof of Theorem 2. □
Proof of Theorem 3 It suffices to prove for and some constant that the following inequality holds:
Fix a cube and . Write, for and ,
Then
For , by Hölder’s inequality, we get
For , choose such that , by Hölder’s inequality and -boundedness of , we obtain
For , recalling that , taking with , by Hölder’s inequality, we obtain
This completes the proof of Theorem 3. □
Proof of Theorem 4 Choose in Theorem 1 and let , then , thus we have, by Lemmas 1, 3, and 4,
This completes the proof of Theorem 4. □
Proof of Theorem 5 Choose in Theorem 1 and let , then , thus we have, by Lemmas 5-7,
This completes the proof of Theorem 5. □
Proof Theorem 6 Choose in Theorem 2. By using Lemma 2, we obtain
This completes the proof of Theorem 6. □
Proof of Theorem 7 Choose in Theorem 3 and similar to the proof of Theorem 4, we have
This completes the proof of the theorem. □
Proof of Theorem 8 Choose in Theorem 3 and similar to the proof of Theorem 5, we have
This completes the proof of the theorem. □
References
Coifman R, Rochberg R, Weiss G: Factorization theorems for Hardy spaces in several variables. Ann. Math. 1976, 103: 611–635. 10.2307/1970954
Chanillo S: A note on commutators. Indiana Univ. Math. J. 1982, 31: 7–16. 10.1512/iumj.1982.31.31002
Di Fazio G, Ragusa MA: Commutators and Morrey spaces. Boll. Unione Mat. Ital., A (7) 1991, 5: 323–332.
Di Fazio G, Ragusa MA: Interior estimates in Morrey spaces for strong solutions to nondivergence form equations with discontinuous coefficients. J. Funct. Anal. 1993, 112: 241–256. 10.1006/jfan.1993.1032
Janson S: Mean oscillation and commutators of singular integral operators. Ark. Mat. 1978, 16: 263–270. 10.1007/BF02386000
Liu LZ: Interior estimates in Morrey spaces for solutions of elliptic equations and weighted boundedness for commutators of singular integral operators. Acta Math. Sci. 2005,25(1):89–94.
Pérez C, Trujillo-Gonzalez R: Sharp weighted estimates for multilinear commutators. J. Lond. Math. Soc. 2002, 65: 672–692. 10.1112/S0024610702003174
Chen WG: Besov estimates for a class of multilinear singular integrals. Acta Math. Sin. 2000, 16: 613–626. 10.1007/s101140000059
Paluszynski M: Characterization of the Besov spaces via the commutator operator of Coifman, Rochberg and Weiss. Indiana Univ. Math. J. 1995, 44: 1–17.
Chang DC, Li JF, Xiao J: Weighted scale estimates for Calderón-Zygmund type operators. Contemp. Math. 2007, 446: 61–70.
Lin Y: Sharp maximal function estimates for Calderón-Zygmund type operators and commutators. Acta Math. Sci. Ser. A Chin. Ed. 2011, 31: 206–215.
Garcia-Cuerva J, Rubio de Francia JL North-Holland Mathematics Studies 16. In Weighted Norm Inequalities and Related Topics. North-Holland, Amsterdam; 1985.
Stein EM: Harmonic Analysis: Real Variable Methods, Orthogonality and Oscillatory Integrals. Princeton University Press, Princeton; 1993.
Peetre J: On the theory of -spaces. J. Funct. Anal. 1969, 4: 71–87. 10.1016/0022-1236(69)90022-6
Chiarenza F, Frasca M: Morrey spaces and Hardy-Littlewood maximal function. Rend. Mat. 1987, 7: 273–279.
Mizuhara T: Boundedness of some classical operators on generalized Morrey spaces. Harmonic Analysis. ICM-90Satellite Conference Proceedings (Sendai, 1990) pp. 183-189 (1991).
Muckenhoupt B, Wheeden RL: Weighted norm inequalities for fractional integral. Trans. Am. Math. Soc. 1974, 192: 261–274.
Coifman R, Rochberg R: Another characterization of . Proc. Am. Math. Soc. 1980, 79: 249–254. 10.1090/S0002-9939-1980-0565349-8
Acknowledgements
Project supported by Hunan Provincial Natural Science Foundation of China (12JJ6003) and Scientific Research Fund of Hunan Provincial Education Departments (12K017).
Author information
Authors and Affiliations
Corresponding author
Additional information
Competing interests
The authors declare that they have no competing interests.
Authors’ contributions
The authors completed the paper together. They also read and approved the final manuscript.
Rights and permissions
Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0), which permits use, duplication, adaptation, distribution, and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
About this article
Cite this article
Gu, G., Cai, M. Sharp maximal function inequalities and boundedness for commutators related to generalized fractional singular integral operators. J Inequal Appl 2014, 211 (2014). https://doi.org/10.1186/1029-242X-2014-211
Received:
Accepted:
Published:
DOI: https://doi.org/10.1186/1029-242X-2014-211