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Related papers: Computability of a Whitney Extension

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Let $C$ be a subset of $\mathbb{R}^n$ (not necessarily convex), $f:C\to\mathbb{R}$ be a function, and $G:C\to\mathbb{R}^n$ be a uniformly continuous function, with modulus of continuity $\omega$. We provide a necessary and sufficient…

Classical Analysis and ODEs · Mathematics 2016-10-11 Daniel Azagra , Carlos Mudarra

We study a variant of the Whitney extension problem for the space $C^{k,\omega}(R^n)$. We identify this space with a space of Lipschitz mappings from $R^n$ into the space $P_k \times R^n$ of polynomial fields on $R^n$ equipped with a…

Functional Analysis · Mathematics 2007-05-23 Pavel Shvartsman

By combining well-known techniques from both noncommutative algebra and computational commutative algebra, we observe that an algorithmic approach can be applied to the study of irreducible representations of finitely presented algebras. In…

Rings and Algebras · Mathematics 2007-05-23 Edward S. Letzter

Whitney's extension problem, i.e., how one can tell whether a function $f : X \to \mathbb R$, $X \subseteq \mathbb R^n$, is the restriction of a $C^m$-function on $\mathbb R^n$, was solved in full generality by Charles Fefferman in 2006. In…

Logic · Mathematics 2025-07-02 Adam Parusiński , Armin Rainer

The purpose of this paper is to address a manifold-based version of Whitney's extension problem: Given a compact set $E\subset\mathbb{R}^n$, how can we tell if there exists a $d$-dimensional, $C^m$-smooth manifold $\mathcal{M}\supset E$? We…

Functional Analysis · Mathematics 2024-01-09 Kevin O'Neill

In this announcement we consider the following problem. Let $n,m\geq 1$, $U\subset\mathbb R^n$ open. In this paper we provide a sharp solution to the following Whitney distortion extension problems: (a) Let $\phi:U\to \mathbb R^n$ be a…

Classical Analysis and ODEs · Mathematics 2024-02-27 S. B Damelin , C. Fefferman

Given $X$ a Hilbert space, $\omega$ a modulus of continuity, $E$ an arbitrary subset of $X$, and functions $f:E\to\mathbb{R}$, $G:E\to X$, we provide necessary and sufficient conditions for the jet $(f,G)$ to admit an extension $(F, \nabla…

Functional Analysis · Mathematics 2017-12-15 Daniel Azagra , Erwan Le Gruyer , Carlos Mudarra

We extend the Theory of Computation on real numbers, continuous real functions, and bounded closed Euclidean subsets, to compact metric spaces $(X,d)$: thereby generically including computational and optimization problems over higher types,…

Logic in Computer Science · Computer Science 2017-03-28 Chansu Park , Ji-Won Park , Sewon Park , Dongseong Seon , Martin Ziegler

Let $\phi$ be a conformal map of the unit disk onto a domain $D$, and suppose $\phi$ has a boundary extension. We show that arbitrarily good approximations of the boundary extension of $\phi$ can be computed from sufficiently good…

Complex Variables · Mathematics 2019-02-20 Timothy H. McNicholl

We prove a computable version of de Finetti's theorem on exchangeable sequences of real random variables. As a consequence, exchangeable stochastic processes expressed in probabilistic functional programming languages can be automatically…

Logic · Mathematics 2012-02-03 Cameron E. Freer , Daniel M. Roy

We prove a version of Whitney's extension theorem in the ultradifferentiable Beurling setting with controlled loss of regularity. As a by-product we show the existence of continuous linear extension operators on certain spaces of Whitney…

Classical Analysis and ODEs · Mathematics 2021-01-08 Armin Rainer

For a closed real algebraic plane affine curve dividing its complexification and equipped with a complex orientation, the Whitney number is expressed in terms of behavior of its complexification at infinity.

Algebraic Geometry · Mathematics 2007-05-23 Oleg Viro

We consider a global, nonlinear version of the Whitney extension problem for manifold-valued smooth functions on closed domains $C$, with non-smooth boundary, in possibly non-compact manifolds. Assuming $C$ is a submanifold with corners, or…

Differential Geometry · Mathematics 2022-09-13 David Michael Roberts , Alexander Schmeding

Using appropriate notation systems for proofs, cut-reduction can often be rendered feasible on these notations, and explicit bounds can be given. Developing a suitable notation system for Bounded Arithmetic, and applying these bounds, all…

Logic in Computer Science · Computer Science 2007-12-11 Klaus Aehlig , Arnold Beckmann

In the present paper it is shown that real function $g(x)=\int_{0}^{x}f(t)dt$ is a linear-space computable real function on interval $[0,1]$ if $f$ is a linear-space computable $C^2[0,1]$ real function on interval $[0,1]$, and this result…

Computational Complexity · Computer Science 2014-11-18 Sergey V. Yakhontov

Let $X$ denote a Hilbert space. Given a compact subset $K$ of $X$ and two continuous functions $f:K\to\mathbb{R}$, $G:K\to X$, we show that a necessary and sufficient condition for the existence of a convex function $F\in C^1(X)$ such that…

Functional Analysis · Mathematics 2020-04-03 Daniel Azagra , Carlos Mudarra

A computably presented algebraic field $F$ has a \emph{splitting algorithm} if it is decidable which polynomials in $F[X]$ are irreducible there. We prove that such a field is computably categorical iff it is decidable which pairs of…

Logic · Mathematics 2018-02-12 Russell Miller , Alexandra Shlapentokh

The Whitney extension theorem is a classical result in analysis giving a necessary and sufficient condition for a function defined on a closed set to be extendable to the whole space with a given class of regularity. It has been adapted to…

Metric Geometry · Mathematics 2018-03-16 Nicolas Juillet , Mario Sigalotti

Cost functions provide a framework for constructions of sets Turing below the halting problem that are close to computable. We carry out a systematic study of cost functions. We relate their algebraic properties to their expressive…

Logic · Mathematics 2017-03-07 Andre Nies

This article is a fundamental study in computable measure theory. We use the framework of TTE, the representation approach, where computability on an abstract set X is defined by representing its elements with concrete "names", possibly…

Logic in Computer Science · Computer Science 2015-07-01 Klaus Weihrauch , Nazanin Tavana-Roshandel