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Related papers: Embeddings of $\alpha$-modulation spaces

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Let $X$ be a smooth, irreducible, projective algebraic surface, and let $\alpha \in \mathbb{Q}[m]_{>0}$ be a polynomial. In this paper, we determine topological and geometric properties of the moduli space of $\alpha$-stable coherent…

Algebraic Geometry · Mathematics 2026-03-23 L. Costa , I. Macías Tarrío , L. Roa-Leguizamón

A new construction of decomposition smoothness spaces of homogeneous type is considered. The smoothness spaces are based on structured and flexible decompositions of the frequency space $\mathbb{R}^d\backslash\{0\}$. We construct simple…

Functional Analysis · Mathematics 2017-12-20 Zeineb Al-Jawahri , Morten Nielsen

This is the addendum to the paper "On the Multiplicity Problem and the Isomorphism Problem for the Four Subspace Algebra" Communications in Algebra, 40:6 (2012), 2005-2036 (DOI: 10.1080/00927872.2011.570830). We give here the full proof of…

Representation Theory · Mathematics 2012-07-10 Andrzej Mróz

We prove that if $\omega _1$ and $\omega _2$ are moderate weights and $\mascB$ is a suitable (quasi-)Banach function space, then a necessary and sufficient condition for the embedding $i\, :\, M (\omega _1,\mascB )\to M (\omega _2,\mascB )$…

Functional Analysis · Mathematics 2018-04-04 Christine Pfeuffer , Joachim Toft

In this paper, we study moduli spaces of 2-dimensional complex associative algebras. We give a complete calculation of the cohomology of every element in the moduli space, as well as compute their versal deformations.

In this paper, we give the necessary and sufficient conditions for the boundedness of fractional integral operators on the modulation spaces.

Functional Analysis · Mathematics 2007-07-04 Mitsuru Sugimoto , Naohito Tomita

The main purpose of the paper is to study sharp estimates of approximation of periodic functions in the H\"older spaces $H_p^{r,\alpha}$ for all $0<p\le\infty$ and $0<\alpha\le r$. By using modifications of the classical moduli of…

Classical Analysis and ODEs · Mathematics 2015-07-28 Yurii Kolomoitsev , Jürgen Prestin

We give the sharp conditions for boundedness of Hausdorff operators on certain modulation and Wiener amalgam spaces.

Classical Analysis and ODEs · Mathematics 2018-11-14 Guoping Zhao , Dashan Fan , Weichao Guo

In this paper, we obtain the sharp conditions of the inclusion relations between modulation spaces $M_{p,q}^s$ and Triebel-Lizorkin spaces $F_{p,r}$ for $p\leq 1$, which greatly improve and extend the results for the embedding relations…

Classical Analysis and ODEs · Mathematics 2016-09-20 Weichao Guo , Huoxiong Wu , Guoping Zhao

Modular exponentiation is crucial to number theory and cryptography, yet remains largely unexplored from a mechanistic interpretability standpoint. We train a 4-layer encoder-decoder Transformer model to perform this operation and…

Machine Learning · Computer Science 2025-10-24 David Demitri Africa , Sara M. Kapoor , Theo Simon Sorg , Challenger Mishra

By a new method derived from Nicola--Primo--Tabacco[24], we study the boundedness on $\alpha$-modulation spaces of unimodular multipliers with symbol $e^{i\mu(\xi)}$. Comparing with the previous results, the boundedness result is…

Classical Analysis and ODEs · Mathematics 2019-03-19 Guoping Zhao , Weichao Guo

We investigate the boundedness of unimodular Fourier multipliers on modulation spaces. Surprisingly, the multipliers with general symbol $e^{i|\xi|^\alpha}$, where $\alpha\in[0, 2]$, are bounded on all modulation spaces, but, in general,…

Functional Analysis · Mathematics 2011-04-27 Arpad Benyi , Karlheinz Gröchenig , Kasso Okoudjou , Luke Rogers

We indicate how to construct a family of modulation function spaces that have a scaling symmetry. We also illustrate the behavior of the Schr\"odinger multiplier on such function spaces.

Functional Analysis · Mathematics 2019-09-04 Árpád Bényi , Tadahiro Oh

In a recent paper, we have shown that warped time-frequency representations provide a rich framework for the construction and study of smoothness spaces matched to very general phase space geometries obtained by diffeomorphic deformations…

Functional Analysis · Mathematics 2024-07-24 Nicki Holighaus , Felix Voigtlaender

For Hardy spaces and weighted Bergman spaces on the open unit ball in ${\mathbb C}^n$, we determine exactly when $A^p_\alpha\subset H^q$ or $H^p\subset A^q_\alpha$, where $0<q<\infty$, $0<p<\infty$, and $-\infty<\alpha<\infty$. For each…

Complex Variables · Mathematics 2025-02-13 Guanlong Bao , Pan Ma , Fugang Yan , Kehe Zhu

In the present paper we study the representations of the Jacobi algebra. More concretely, we define, analogously to the case of semi-simple Lie algebras, the Verma modules over the Jacobi algebra ${\cal G}_2$. We study their reducibility…

Representation Theory · Mathematics 2021-11-03 N. Aizawa , V. K. Dobrev , S. Doi

We prove that the forgetful morphism from the moduli space of orthogonal bundles to the moduli space of vector bundles over a smooth curve is an embedding. Our proof relies on an explicit description of a set of generators for the…

Algebraic Geometry · Mathematics 2007-05-23 Olivier Serman

Motivated by the study of the local extrema of sin(x)/x we define the \emph{Amplitude Modulation} transform of functions defined on (subsets of) the real line. We discuss certain properties of this transform and invert it in some easy…

Classical Analysis and ODEs · Mathematics 2007-05-23 Igor Rivin

An important problem in machine learning theory is to understand the approximation and generalization properties of two-layer neural networks in high dimensions. To this end, researchers have introduced the Barron space…

Machine Learning · Statistics 2024-01-02 Lei Wu

We prove embedding theorems for fully anisotropic Besov spaces. More concrete, inequalities between modulus of continuity in different metrics and of Sobolev type are obtained. Our goal is to get sharp estimates for some anisotropic cases…

Functional Analysis · Mathematics 2007-05-23 F. J. Perez Lazaro