Browsing Harmonic Analysis by Title
Now showing items 86-100 of 100
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Three Observations on Commutators of Singular Integral Operators with BMO Functions
(2016-07-01)Three observations on commutators of Singular Integral Operators with BMO functions are exposed, namely 1 - The already known subgaussian local decay for the commutator, namely $\[\frac{1}{|Q|}\left|\left\{x\in Q\, : ... -
Topics in Harmonic Analysis; commutators and directional singular integrals
(2020-03-01)This dissertation focuses on two main topics: commutators and maximal directional operators. Our first topic will also distinguish between two cases: commutators of singular integral operators and BMO functions and ... -
Two-weight mixed norm estimates for a generalized spherical mean Radon transform acting on radial functions
(2018)We investigate a generalized spherical means operator, viz. generalized spherical mean Radon transform, acting on radial functions. We establish an integral representation of this operator and find precise estimates of ... -
Uniform maximal Fourier restriction for convex curves
(2024)We extend the estimates for maximal Fourier restriction operators proved by M\"{u}ller, Ricci, and Wright in \cite{MR3960255} and Ramos in \cite{MR4055940} to the case of arbitrary convex curves in the plane, with constants ... -
Unique determination of the electric potential in the presence of a fixed magnetic potential in the plane
(2018-12)For electric and magnetic potentials with compact support, we consider the magnetic Schrödinger equation with fixed positive energy. Under a mild additional regularity hypothesis, and with fixed magnetic potential, we show ... -
Variation bounds for spherical averages
(2021-06-22)We consider variation operators for the family of spherical means, with special emphasis on $L^p\to L^q$ estimates -
Vector-valued extensions for fractional integrals of Laguerre expansions
(2018)We prove some vector-valued inequalities for fractional integrals defined for several orthonormal systems of Laguerre functions. On the one hand, we obtain weighted $L^p-L^q$ vector-valued extensions, in a multidimensional ... -
Vector-valued operators, optimal weighted estimates and the $C_p$ condition
(2018-09)In this paper some new results concerning the $C_p$ classes introduced by Muckenhoupt and later extended by Sawyer, are provided. In particular we extend the result to the full range expected $p>0$, to the weak norm, to ... -
Walter Rudin meets Elias M. Stein
(2023)Walter Rudin and Elias M. Stein were giants in the world of mathemat- ics. They were loved and admired from students and researchers to teachers and academics, both young and old. They touched many of us through ... -
Weak and strong $A_p$-$A_\infty$ estimates for square functions and related operators
(2017-07)We prove sharp weak and strong type weighted estimates for a class of dyadic operators that includes majorants of both standard singular integrals and square functions. Our main new result is the optimal bound $[w]_{A_p} ... -
Weak-type maximal function estimates on the infinite-dimensional torus
(2023-07)We prove necessary and sufficient conditions for the weak- $L^p$ boundedness, for $p\in (1,\infty)$, of a maximal operator on the infinite-dimensional torus. In the endpoint case $p=1$ we obtain the same weak-type inequality ... -
Weighted BMO estimates for singular integrals and endpoint extrapolation in Banach function spaces
(2023-05-01)In this paper we prove sharp weighted BMO estimates for singular integrals, and we show how such estimates can be extrapolated to Banach function spaces. -
Weighted Lorentz spaces: Sharp mixed A<inf>p</inf> − A<inf>∞</inf> estimate for maximal functions
(2023-03-15)We prove the sharp mixed Ap−A∞ weighted estimate for the Hardy-Littlewood maximal function in the context of weighted Lorentz spaces, namely [Formula presented] where [Formula presented]. Our method is rearrangement free ... -
Weighted mixed weak-type inequalities for multilinear operators
(2017)In this paper we present a theorem that generalizes Sawyer's classic result about mixed weighted inequalities to the multilinear context. Let $\vec{w}=(w_1,...,w_m)$ and $\nu = w_1^\frac{1}{m}...w_m^\frac{1}{m}$, the main ... -
Weighted norm inequalities for rough singular integral operators
(2018-08-17)In this paper we provide weighted estimates for rough operators, including rough homogeneous singular integrals $T_\Omega$ with $\Omega\in L^\infty(\mathbb{S}^{n-1})$ and the Bochner--Riesz multiplier at the critical index ...