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Related papers: A dichotomy for Borel functions

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We investigate classes of functions from a topological space to a metric space that are related to those of Borel class 1. Following the idea defining an equi-Baire 1 family (due to Lecomte) we define the respective equi-families of…

General Topology · Mathematics 2026-03-25 Marek Balcerzak , Ľubica Holá , Olena Karlova , Piotr Szuca

In this paper, we show that Frucht's theorem holds in Borel setting. More specifically, we prove that any standard Borel group can be realized as the Borel automorphism group of a Borel graph. A slight modification of our construction also…

Logic · Mathematics 2022-05-16 Onur Bilge , Burak Kaya

This is a continuation of recent work on the general definition of pseudo-differential operators of type $1,1$, in H\"ormander's sense. Continuity in $L_p$-Sobolev spaces and H\"older--Zygmund spaces, and more generally in Besov and…

Analysis of PDEs · Mathematics 2016-09-27 Jon Johnsen

We present dichotomy theorems regarding the computational complexity of counting fixed points in boolean (discrete) dynamical systems, i.e., finite discrete dynamical systems over the domain {0,1}. For a class F of boolean functions and a…

Computational Complexity · Computer Science 2008-12-02 Christopher M. Homan , Sven Kosub

We introduce a functor of functionals which preserve maximum of comonotone functions and addition of constants. This functor is a subfunctor of the functor of order-preserving functionals and contains the idempotent measure functor as…

General Topology · Mathematics 2025-04-21 Taras Radul

In this article we treat a notion of continuity for a multi-valued function $F$ and we compute the descriptive set-theoretic complexity of the set of all $x$ for which $F$ is continuous at $x$. We give conditions under which the latter set…

Logic · Mathematics 2015-07-01 Vassilios Gregoriades

We prove a Kadec-Pelczy\'nski dichotomy-type theorem for bounded sequences in the predual of a JBW*-algebra, showing that for each bounded sequence $(\phi_n)$ in the predual of a JBW$^*$-algebra $M$, there exist a subsequence…

Operator Algebras · Mathematics 2012-11-22 Francisco J. FernÁndez-Polo , Antonio M. Peralta , MarÍa Isabel RamÍrez

A complete classification of the computational complexity of the fixed-point existence problem for boolean dynamical systems, i.e., finite discrete dynamical systems over the domain {0, 1}, is presented. For function classes F and graph…

Computational Complexity · Computer Science 2008-12-01 Sven Kosub

We examine when the composition of two entire functions f and g is even, and extend some of our results to cyclic compositions in general. We prove some theorems for the cases when f or g is a polynomial. Two of the key theorems we use are…

Complex Variables · Mathematics 2007-05-23 Alan L. Horwitz

We prove results that falsify Silver's dichotomy for Borel equivalence relations on the generalised Baire space under the assumption V=L.

Logic · Mathematics 2014-08-20 Sy-David Friedman , Vadim Kulikov

We present an explicit formula for the discrete power function introduced by Bobenko, which is expressed in terms of the hypergeometric \tau functions for the sixth Painlev\'e equation. The original definition of the discrete power function…

Exactly Solvable and Integrable Systems · Physics 2012-01-27 Hisashi Ando , Mike Hay , Kenji Kajiwara , Tetsu Masuda

In this expository paper we describe a powerful combinatorial formula and its implications in geometry, topology, and algebra. This formula first appeared in the appendix of a book by Andersen, Jantzen, and Soergel. Sara Billey discovered…

Combinatorics · Mathematics 2013-09-03 Julianna S. Tymoczko

It is shown that that for every Darboux function $F$ there is a non-constant continuous function $f$ such that $F+f$ is still Darboux. It is shown to be consistent --- the model used is iterated Sacks forcing --- that for every Darboux…

Logic · Mathematics 2008-02-03 Juris Steprāns

This is a literal word-for-word translation from the French of Phragmen's proof (the first such published) of Weierstrass' famous theorem characterizing all analytic functions which possess an algebraic addition theorem.

History and Overview · Mathematics 2012-12-27 Edvard Phragmen

Using a variation of the Murphy-Varopoulos Theorem, we give a new proof of the following R.J.Loy Theorem: Let A be a separable Banach*-algebra with center Z such that ZA has at most countable codimension, then every positive linear…

Functional Analysis · Mathematics 2014-04-30 M. El Azhari

A classical theorem due to Borel asserts that any formal serie with real coefficients is the Taylor expansion of a germ of $\mathcal{C}^{\infty}- {\rm function}$. We study such a problem in the context of Lie algebras of vector fields or of…

Dynamical Systems · Mathematics 2017-10-26 D. Cerveau , D. Garba Belko

We show that the sign constancy for the values of certain weighted summatory functions of the von Mangoldt function implies the Riemann hypothesis or the generalized Riemann hypothesis for Dirichlet $L$-functions. While such sign constancy…

Number Theory · Mathematics 2025-11-11 Masatoshi Suzuki

The main subject of the paper is the so-called Discrete Painlev\'e-1 Equation (DP1). Solutions of the DP1 are classified under criterion of their behavior while argument tends to infinity. The appropriate theorems of existence are proved.

High Energy Physics - Theory · Physics 2007-05-23 V. L. Vereschagin

The Dirichlet problem for a class of stochastic partial differential equations is studied in Sobolev spaces. The existence and uniqueness result is proved under certain compatibility conditions that ensure the finiteness of…

Probability · Mathematics 2018-05-18 Kai Du

We determine the Bohr radius for the class of all functions $f$ of the form $f(z)=\sum_{k=1}^\infty a_{kp+m} z^{kp+m}$ analytic in the unit disk $|z|<1$ and satisfy the condition $|f(z)|\le 1$ for all $|z|<1$. In particular, our result also…

Complex Variables · Mathematics 2017-08-21 Ilgiz R Kayumov , Saminathan Ponnusamy