Skip to Main Content

Transactions of the American Mathematical Society

Published by the American Mathematical Society since 1900, Transactions of the American Mathematical Society is devoted to longer research articles in all areas of pure and applied mathematics.

ISSN 1088-6850 (online) ISSN 0002-9947 (print)

The 2020 MCQ for Transactions of the American Mathematical Society is 1.48.

What is MCQ? The Mathematical Citation Quotient (MCQ) measures journal impact by looking at citations over a five-year period. Subscribers to MathSciNet may click through for more detailed information.

 

Matrix-weighted Besov spaces
HTML articles powered by AMS MathViewer

by Svetlana Roudenko PDF
Trans. Amer. Math. Soc. 355 (2003), 273-314 Request permission

Abstract:

Nazarov, Treil and Volberg defined matrix $A_p$ weights and extended the theory of weighted norm inequalities on $L^p$ to the case of vector-valued functions. We develop some aspects of Littlewood-Paley function space theory in the matrix weight setting. In particular, we introduce matrix- weighted homogeneous Besov spaces $\dot {B}^{\alpha q}_p(W)$ and matrix-weighted sequence Besov spaces $\dot {b}^{\alpha q}_p(W)$, as well as $\dot {b}^{\alpha q}_p(\{A_Q\})$, where the $A_Q$ are reducing operators for $W$. Under any of three different conditions on the weight $W$, we prove the norm equivalences $\Vert \vec {f} \Vert _{\dot {B}^{\alpha q}_p(W)} \approx \Vert \{ \vec {s}_Q \}_Q \Vert _{\dot {b}^{\alpha q}_p(W)} \approx \Vert \{ \vec {s}_Q \}_Q \Vert _{\dot {b}^{\alpha q}_p(\{A_Q\})}$, where $\{ \vec {s}_Q \}_Q$ is the vector-valued sequence of $\varphi$-transform coefficients of $\vec {f}$. In the process, we note and use an alternate, more explicit characterization of the matrix $A_p$ class. Furthermore, we introduce a weighted version of almost diagonality and prove that an almost diagonal matrix is bounded on $\dot {b}^{\alpha q}_p(W)$ if $W$ is doubling. We also obtain the boundedness of almost diagonal operators on $\dot {B}^{\alpha q}_p(W)$ under any of the three conditions on $W$. This leads to the boundedness of convolution and non-convolution type Calderón-Zygmund operators (CZOs) on $\dot {B}^{\alpha q}_p(W)$, in particular, the Hilbert transform. We apply these results to wavelets to show that the above norm equivalence holds if the $\varphi$-transform coefficients are replaced by the wavelet coefficients. Finally, we construct inhomogeneous matrix-weighted Besov spaces $B^{\alpha q}_p(W)$ and show that results corresponding to those above are true also for the inhomogeneous case.
References
Similar Articles
Additional Information
  • Svetlana Roudenko
  • Affiliation: Department of Mathematics, Michigan State University, East Lansing, Michigan 48824
  • Address at time of publication: Department of Mathematics, Duke University, Box 90320, Durham, North Carolina 27708
  • MR Author ID: 701923
  • Email: svetlana@math.msu.edu
  • Received by editor(s): March 15, 2002
  • Published electronically: August 7, 2002
  • © Copyright 2002 American Mathematical Society
  • Journal: Trans. Amer. Math. Soc. 355 (2003), 273-314
  • MSC (2000): Primary 42B25, 42B35, 47B37, 47B38
  • DOI: https://doi.org/10.1090/S0002-9947-02-03096-9
  • MathSciNet review: 1928089