English
Related papers

Related papers: Some new light on a few classical results

200 papers

In this paper, we introduce a new concept, namely $\epsilon$-arithmetics, for real vectors of any fixed dimension. The basic idea is to use vectors of rational values (called rational vectors) to approximate vectors of real values of the…

Information Theory · Computer Science 2022-11-28 Xiang-Gen Xia

We study complex interpolation scales obtained by vector valued amalgamation and the derivations they generate. We study their trivial and singular character and obtain examples showing that the hypotheses in the main theorems of [J.M.F.…

Functional Analysis · Mathematics 2018-08-10 Jesús M. F. Castillo , Daniel Morales , Jesús Suárez de la Fuente

Many well-known theorems establish sufficient criteria for linearizability of a vector field in terms of the eigenvalues of its linear approximation. By attaching weights to coordinates so that some directions are considered "linear",…

Differential Geometry · Mathematics 2026-05-14 Arthur Lei Qiu

We give a short proof of Stein's universal multiplier theorem, purely by probabilistic methods, thus avoiding any use of harmonic analysis techniques (complex interpolation or transference methods).

Functional Analysis · Mathematics 2014-08-21 Dario Trevisan

We consider an integral operator $\mathcal{I}$, special instances of which was studied in various contexts. Using an appropriate transformation we write this operator in terms of weighted composition operators. Then, we provide a…

Complex Variables · Mathematics 2012-04-16 Epaminondas Diamantopoulos

By employing harmonic analysis techniques, we derive weak-type Caffarelli-Kohn-Nirenberg inequalities under natural parameter conditions. A key feature of these weak-type versions is that they remain valid even at critical parameter values…

Classical Analysis and ODEs · Mathematics 2026-02-05 Dinghuai Wang

In this paper, we investigate existence and uniqueness of solutions of nonlinear Volterra-Fredholm impulsive integrodifferential equations. Utilizing theory of Picard operators we examine data dependence of solutions on initial conditions…

Classical Analysis and ODEs · Mathematics 2019-08-27 Pallavi U. Shikhare , Kishor D. Kucche , J. Vanterler da C. Sousa

Let $L$ be a linear operator in $L^2(\mathbb{R}^n)$ which generates a semigroup $e^{-tL}$ whose kernels $p_t(x,y)$ satisfy the Gaussian upper bound. In this paper, we investigate several kinds of weighted norm inequalities for the conical…

Classical Analysis and ODEs · Mathematics 2020-11-24 Mingming Cao , Zengyan Si , Juan Zhang

The main object of this paper is to improve some of the known estimates for classical Kantorovich operators. A quantitative Voronovskaya-type result in terms of second moduli of continuity which improves some previous results is obtained.…

Classical Analysis and ODEs · Mathematics 2019-04-26 Ana Maria Acu , Heiner Gonska

In this paper, we obtain two interpolation theorems on convex-set valued Lebesgue spaces, which generalize the Marcinkiewicz interpolation theorem and Riesz-Thorin interpolation theorem on classical Lebesgue spaces, respectively. As…

Functional Analysis · Mathematics 2024-01-02 Yuxun Zhang , Jiang Zhou

We introduce a variant of the $C_p$ condition (denoted by $SC_p$), and show that it characterizes weighted weak type versions of the classical Coifman-Fefferman and Fefferman-Stein inequalities.

Classical Analysis and ODEs · Mathematics 2019-10-17 Andrei K. Lerner

We consider a setting in which it is desired to find an optimal complex vector $\mathbf{x}\in\mathbb{C}^N$ that satisfies $\mathcal{A}(\mathbf{x}) \approx \mathbf{b}$ in a least-squares sense, where $\mathbf{b} \in \mathbb{C}^M$ is a data…

Numerical Analysis · Mathematics 2020-07-21 Tae Hyung Kim , Justin P. Haldar

Calculi with control operators have been studied to reason about control in programming languages and to interpret the computational content of classical proofs. To make these calculi into a real programming language, one should also…

Logic in Computer Science · Computer Science 2012-10-12 Robbert Krebbers

Recently, Hartz proved that every commuting contractive classical multishift with non-zero weights satisfies the matrix-version of von Neumann's inequality. We show that this result does not extend to the class of commuting operator-valued…

Functional Analysis · Mathematics 2018-11-07 Rajeev Gupta , Surjit Kumar , Shailesh Trivedi

The operator-valued multiplier theorems in weighted abstract Besov spaces are studied. These results permit us to show embedding theorems in weighted Besov-Lions type spaces. The most regular class of interpolation space is found such that…

Analysis of PDEs · Mathematics 2017-06-06 Veli Shakhmurov , Rishad Shahmurov

In this article, we prove a weighted Hardy inequality for $1<p<+\infty$ and dimension $d\ge1$. If $p>d$, then we can deduce from our weighted Hardy inequality a Poincar\'e inequality. The proof of the weighted Hardy inequality is based on…

Analysis of PDEs · Mathematics 2012-07-20 Daniel Hauer , Abdelaziz Rhandi

The question of what is genuinely quantum about weak values is only ever going to elicit strongly subjective opinions---it is not a scientific question. Good questions, when comparing theories, are operational---they deal with the…

Quantum Physics · Physics 2014-10-30 Christopher Ferrie , Joshua Combes

We study two weight norm inequalities for a vector-valued operator from a weighted $L^p(\sigma)$-space to mixed norm $L^q_{l^s}(\mu)$ spaces, $1<q<p$. We apply these results to the boundedness of Wolff's potentials.

Classical Analysis and ODEs · Mathematics 2019-02-20 Carme Cascante , Joaquin M. Ortega

Using the log-convexity of the Gamma function and Euler's reflection formula, we give a new proof of a classical weighted sine product inequality. Two different parameter choices yield two competing upper bounds for the same product. We…

General Mathematics · Mathematics 2026-04-16 Augustine L. Mahu , Benoît F. Sehba , Cecilia D. Williams

In this paper, we obtain a new class of functions, which is developed via the Hermite--Hadamard inequality for convex functions. The well-known one-one correspondence between the class of operator monotone functions and operator connections…

Functional Analysis · Mathematics 2021-07-23 R. Pal , M. Singh , M. S. Moslehian , J. S. Aujla