English
Related papers

Related papers: On repeated sequential closures of constructible f…

200 papers

For a Tychonoff space $X$, we will denote by $USC_{p}(X)$ ($B_1(X)$) a set of all real-valued upper semicontinuous functions (a set of all Baire functions of class 1) defined on $X$ endowed with the pointwise convergence topology. In this…

General Topology · Mathematics 2018-09-27 Alexander V. Osipov , Evgenii G. Pytkeev

We construct a function for almost-complex Riemannian manifolds. Non-vanishing of the function for the almost-complex structure implies the almost-complex structure is not integrable. Therefore the constructed function is an obstruction for…

General Mathematics · Mathematics 2019-03-11 Jun Ling

Sequentiable structures are a subclass of monoids that generalise the free monoids and the monoid of non-negative real numbers with addition. In this paper we consider functions $f:\Sigma^*\rightarrow {\cal M}$ and define the Myhill-Nerode…

Formal Languages and Automata Theory · Computer Science 2017-06-12 Stefan Gerdjikov , Stoyan Mihov

Numerably contractible spaces play an important role in the theory of homotopy pushouts and pullbacks. The corresponding results imply that a number of well known weak homotopy equivalences are genuine ones if numerably contractible spaces…

Algebraic Topology · Mathematics 2014-10-01 E. Schwamberger , R. Vogt

For a Tychonoff space $X$, we denote by $C_k(X)$ the space of all real-valued continuous functions on X with the compact-open topology. In this paper, we have gave characterization for $C_k(X)$ to satisfy $S_{fin}(S, S)$.

General Topology · Mathematics 2018-05-16 Alexander V. Osipov

We consider rationally connected complex projective manifolds M and show that their loop spaces--infinite dimensional complex manifolds--have properties similar to those of M. Furthermore, we give a finite dimensional application concerning…

Algebraic Geometry · Mathematics 2007-05-23 L. Lempert , E. Szabo

We prove the following two results. 1. If $X$ is a completely regular space such that for every topological space $Y$ each separately continuous function $f:X\times Y\to\mathbb R$ is of the first Baire class, then every Lindel\"of subspace…

General Topology · Mathematics 2016-01-21 V. V. Mykhaylyuk

A fundamental open question asking whether all real-valued strongly quasiconvex functions defined on $\mathbb R^n$ are necessarily continuous, akin to their convex counterparts, is answered in detail in this paper. Among other things, we…

Optimization and Control · Mathematics 2025-12-04 Nguyen Thi Van Hang , Felipe Lara , Nguyen Dong Yen

All continuous translation invariant complex-valued valuations on Lebesgue measurable functions are completely classified. And all continuous rotation invariant complex-valued valuations on spherical Lebesgue measurable functions are also…

Metric Geometry · Mathematics 2020-06-12 Lijuan Liu

The definition of conservative-irreversible functions is extended to smooth manifolds. The local representation of these functions is studied and reveals that not each conservative-irreversible function is given by the weighted product of…

Mathematical Physics · Physics 2024-04-09 Dan Goreac , Jonas Kirchhoff , Bernhard Maschke

We characterize order preserving continuous surjections between compact linearly ordered spaces which admit an averaging operator, together with estimates of the norm of such an operator. This result is used to the study of strengthenings…

Functional Analysis · Mathematics 2012-10-23 Wieslaw Kubiś , Ondrej Kalenda

By using a similar pattern of arguments, we show that in three categories the collection of isomorphisms forms a residual subset of the space of morphisms. We first consider surjective continuous mappings on Cantor spaces. Next, we look at…

Dynamical Systems · Mathematics 2026-03-30 Ethan Akin , Benjamin Weiss

Reversibility is a key issue in the interface between computation and physics, and of growing importance as miniaturization progresses towards its physical limits. Most foundational work on reversible computing to date has focussed on…

Logic in Computer Science · Computer Science 2011-12-01 Samson Abramsky

Every computable function has to be continuous. To develop computability theory of discontinuous functions, we study low levels of the arithmetical hierarchy of nonuniformly computable functions on Baire space. First, we classify…

Logic · Mathematics 2013-09-10 Kojiro Higuchi , Takayuki Kihara

We prove a theorem which provides a method for constructing points on varieties defined by certain smooth functions. We require that the functions are definable in a definably complete expansion of a real closed field and are locally…

Logic · Mathematics 2014-02-26 G. O. Jones , A. J. Wilkie

We give characterizations of unital uniform topological algebras and saturated locally multiplicatively convex algebras by means of multiplicative linear functionals. Some automatic continuity theorems in advertibly complete uniform…

Functional Analysis · Mathematics 2014-01-03 M. El Azhari

We are considering typed hierarchies of total, continuous functionals using complete, separable metric spaces at the base types. We pay special attention to the so called Urysohn space constructed by P. Urysohn. One of the properties of the…

Logic in Computer Science · Computer Science 2015-07-01 Dag Normann

In this article we investigate some general properties of the multiplier algebras of normed spaces of continuous functions (NSCF). In particular, we prove that the multiplier algebra inherits some of the properties of the NSCF. We show that…

Functional Analysis · Mathematics 2020-09-25 Eugene Bilokopytov

We study projective functions. We prove that projective functions generalise lower and upper-semianalytic ones while being stable by composition and difference. We show that the class of projective functions is closed under sums,…

Logic · Mathematics 2025-10-14 Laurence Carassus , Massinissa Ferhoune

We consider Bergman spaces and variations of them in one or several complex variables. For some domains we show that in these spaces the generic function is totally unbounded and hence non - extendable. We also show that the generic…

Complex Variables · Mathematics 2017-04-10 T. Hatziafratis , K. Kioulafa , V. Nestoridis