Results 41 to 50 of about 105,780 (179)
Қарағанды университетінің хабаршысы. Математика сериясыThe article is dedicated to the issues of studying the approximation of functions by trigonometric polynomials with a spectrum from special sets. In this paper, these special sets are harmonic intervals.
G.A. Yessenbayeva, L.A. Serikova
doaj +1 more source
On the $C^k$-embedding of Lorentzian manifolds in Ricci-flat spaces
, 2018 In this paper we investigate the problem of non-analytic embeddings of Lorentzian manifolds in Ricci-flat semi-Riemannian spaces. In order to do this, we first review some relevant results in the area, and then motivate both the mathematical and physical
Avalos, Rodrigo +2 more
core +1 more source
Современная математика: Фундаментальные направленияWe establish the increased integrability of the gradient of the solution to the Dirichlet problem for the Laplace operator with lower terms and prove the unique solvability of this problem.
Yu. A. Alkhutov, G. A. Chechkin
doaj +1 more source
Sobolev type spaces associated with the q-Rubin's operator
Le Matematiche, 2014 In this paper we introduce and study some $q$-Sobolev type spaces by using the harmonic analysis associated with the q-Rubin operator. In particular, embedding theorems for these spaces are established.
Neji Bettaibi +2 more
doaj
Embeddings between Triebel-Lizorkin Spaces on Metric Spaces Associated with Operators
Analysis and Geometry in Metric Spaces, 2020 We consider the general framework of a metric measure space satisfying the doubling volume property, associated with a non-negative self-adjoint operator, whose heat kernel enjoys standard Gaussian localization.
Georgiadis Athanasios G. +1 more
doaj +1 more source
The Friedman embedding theorem
Journal of Algebra, 2011 The article is a sequel to the same author's article [in J. Group Theory 12, No. 4, 561-565 (2009; Zbl 1215.20034)] which already dealt with the ``Borelness'' of HNN constructions. In the former, the author showed that there exists \textit{no} Borel map \(\varphi\) from the space of countable groups to that of 2-generated groups such that: (1) any ...
openaire +1 more source
Formal Proof of a Machine Closed Theorem in Coq
Journal of Applied Mathematics, 2014 The paper presents a formal proof of a machine closed theorem of TLA+ in the theorem proving system Coq. A shallow embedding scheme is employed for the proof which is independent of concrete syntax.
Hai Wan +3 more
doaj +1 more source
de Sitter in non-supersymmetric string theories: no-go theorems and brane-worlds
Journal of High Energy Physics, 2020 We study de Sitter configurations in ten-dimensional string models where supersymmetry is either absent or broken at the string scale. To this end, we derive expressions for the cosmological constant in general warped flux compactifications with ...
Ivano Basile, Stefano Lanza
doaj +1 more source
Journal of Algebra, 2011 Let \(M\) be a commutative monoid written additively. Recall that \(M\) is \textit{cancellative} if \(a+b=a+c\) implies \(b=c\), \textit{reduced} if the only unit of \(M\) is \(0\), and \textit{torsionfree} (or \textit{torsionless}) if \(na=nb\) implies \(a=b\). An nonunit element \(a\) of a cancellative torsionfree monoid \(M\) is \textit{irreducible}
Coykendall, Jim +1 more
openaire +1 more source
Embedding theorems for Müntz spaces [PDF]
Annales de l'Institut Fourier, 2011 We discuss boundedness and compactness properties of the embedding M Λ 1 ⊂L 1 (μ), where M Λ 1 is the closed linear span of the monomials x λ n in L 1 ([0,1]) and μ is a finite positive Borel measure on the interval [0,1]. In particular, we introduce a class of “sublinear” measures and provide a rather complete solution of the embedding problem for ...
Chalendar, Isabelle +2 more
openaire +3 more sources