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Related papers: The A_2 theorem: Remarks and complements

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We consider the weak to strong type problem for two weight norm inequalities for Calder\'on-Zygmund operators with doubling weights. We show that if a Calder\'on-Zygmund operator T is weak type (2,2) with doubling weights, then it is strong…

Classical Analysis and ODEs · Mathematics 2024-02-09 Michel Alexis , Eric T. Sawyer , Ignacio Uriarte-Tuero

We prove a robust extension of the quantum adiabatic theorem. The theorem applies to systems that have resonances instead of bound states, and to systems for which just an approximation to a bound state is known. To demonstrate the…

Mathematical Physics · Physics 2010-02-24 Alexander Elgart , George Hagedorn

We give a simple proof of the $A_2$ conjecture proved recently by T. Hyt\"onen. Our proof avoids completely the notion of the Haar shift operator, and it is based only on the "local mean oscillation decomposition". Also our proof yields a…

Classical Analysis and ODEs · Mathematics 2012-05-08 Andrei K. Lerner

Let $K$ be the Calder\'on-Zygmund convolution kernel on $\mathbb{R}^d (d\geq2)$. Define the commutator associated with $K$ and $a\in L^\infty(\mathbb{R}^d)$ by \[ T_af(x)=p.v. \int K(x-y)m_{x,y}a\cdot f(y)dy. \] Recently, Grafakos and…

Classical Analysis and ODEs · Mathematics 2015-09-17 Yong Ding , Xudong Lai

We review the quantum adiabatic approximation for closed systems, and its recently introduced generalization to open systems (M.S. Sarandy and D.A. Lidar, e-print quant-ph/0404147). We also critically examine a recent argument claiming that…

Quantum Physics · Physics 2007-05-23 M. S. Sarandy , L. -A. Wu , D. A. Lidar

As a corollary to our main result we deduce sharp A_p$ inequalities for T being either the Hilbert transform in dimension d=1, the Beurling transform in dimension d=2, or a Riesz transform in any dimension d\ge 2. For T_{\ast} the maximal…

Classical Analysis and ODEs · Mathematics 2011-03-30 Tuomas P. Hytönen , Michael T. Lacey , Maria Carmen Reguera , Armen Vagharshakyan

Perfect dyadic operators were first introduced in \cite{AHMTT}, where a local $T(b)$ theorem was proved for such operators. In \cite{AY} it was shown that for every singular integral operator $T$ with locally bounded kernel on $\mathbb{R}^n…

Analysis of PDEs · Mathematics 2016-02-09 Oleksandra V. Beznosova

We give a H\"ormander type $L^2-$estimate for the $\bar{\partial}-$equation with respect to the measure $\delta_\Omega^{-\alpha}dV$, $\alpha<1$, on any bounded pseudoconvex domain with $C^2-$boundary. Several applications to the function…

Complex Variables · Mathematics 2013-03-29 Bo-Yong Chen

We prove a pointwise estimate for positive dyadic shifts of complexity $m$ which is linear in the complexity. This can be used to give a pointwise estimate for Calder\'on-Zygmund operators and to answer a question posed by A. Lerner.…

Classical Analysis and ODEs · Mathematics 2016-05-25 Jose M. Conde-Alonso , Guillermo Rey

We give a weak-type counterpart of the main result in an earlier work of the first author, E. Rela and T. Luque which allows to provide a lower bound for the exponent of the $A_{p}$ constant in terms of the behaviour of the unweighted…

Classical Analysis and ODEs · Mathematics 2019-03-01 Carlos Pérez , Israel P. Rivera-Ríos

We consider L^p two weight inequalities for maximal truncations of dyadic Calderon-Zygmund operators. In the case of one weight being doubling, a characterization is given, and for the general case, sufficient conditions are given,…

Classical Analysis and ODEs · Mathematics 2011-03-30 Michael T. Lacey , Eric T. Sawyer , Ignacio Uriate-Tuero

Perturbation theory with respect to the kinetic energy of the heavy component of a two-component quantum system is introduced. An effective Hamiltonian that is accurate to second order in the inverse heavy mass is derived. It contains a new…

Quantum Physics · Physics 2024-06-21 Ryan Requist

We find the exact Bellman function for the weak $L^1$ norm of local positive dyadic shifts. We also describe a sequence of functions, self-similar in nature, which in the limit extremize the local weak-type (1,1) inequality.

Classical Analysis and ODEs · Mathematics 2018-11-06 Guillermo Rey , Alexander Reznikov

Following the ideas of A. Lerner, F. Nazarov, S. Ombrosi from [12] we prove that there is a sequence of weights $w\in A^d_1$ such that $[w]^d_{A_1}\to \infty$, and martingale transforms $T$ such that with an absolute positive $c$ $\|T:…

Analysis of PDEs · Mathematics 2018-04-10 Paata Ivanisvili , Alexander Volberg

We revisit the time-adiabatic theorem of quantum mechanics and show that it can be extended to weakly nonlinear situations, that is to nonlinear Schroedinger equations in which either the nonlinear coupling constant or, equivalently, the…

Mathematical Physics · Physics 2015-02-25 Christof Sparber

We consider weak solutions of the adjoint equation for an elliptic operator in nondivergent form, and their asymptotic properties at an interior point. We assume that the coefficients a_{ij} are bounded, measurable, complex-valued functions…

Analysis of PDEs · Mathematics 2007-05-23 Vladimir Maz'ya , Robert McOwen

Several misprints and small mistakes were in the initial version. They have been corrected. Following the recent experimental realization of synthetic gauge magnetic forces, Jean Dalibard adressed the question whether the adiabatic ansatz…

Analysis of PDEs · Mathematics 2012-01-24 Amandine Aftalion , Francis Nier

Let $A_p(G)$ denote the Figa-Talamanca-Herz Banach Algebra of the locally compact group $G$, thus $A_2(G)$ is the Fourier Algebra of $G$. If $G$ is commutative then $A_2(G)=L^1(\hat{G}){\hat{}}$. Let $A^r_p(G)=A_p\cap L^r(G)$ with norm…

Functional Analysis · Mathematics 2017-03-27 Edmond E. Granirer

We prove strong-type $A_p$-$A_\infty$ estimate for square functions, improving on the $ A_p$ bound due to Lerner. Entropy bounds, in the recent innovation of Treil-Volberg, are then proved. The techniques of proof include parallel stopping…

Classical Analysis and ODEs · Mathematics 2016-11-04 Michael T. Lacey , Kangwei Li

In Theorem 3.1 of [12], we proved a rigidity result for self-shrinkers under the integral condition on the norm of the second fundamental form. In this paper, we relax the such bound to any finite constant (see Theorem 4.4 for details).

Differential Geometry · Mathematics 2023-12-27 Qi Ding