English
Related papers

Related papers: Computability of the Radon-Nikodym derivative

200 papers

We begin the systematic study of decision problems for finitely generated groups given by a solution to their word problem. We relate this to the study of computable analysis on the space of marked groups. We point out that several distinct…

Group Theory · Mathematics 2025-01-15 Emmanuel Rauzy

The notion of weak truth-table reducibility plays an important role in recursion theory. In this paper, we introduce an elaboration of this notion, where a computable bound on the use function is explicitly specified. This elaboration…

Logic · Mathematics 2019-09-04 Kohtaro Tadaki

We study when the integration maps of vector measures can be computed as pointwise limits of their finite rank Radon-Nikod\'ym derivatives. We will show that this can sometimes be done, but there are also principal cases in which this…

Functional Analysis · Mathematics 2017-04-24 Eduardo Jimenez Fernandez , Enrique A. Sanchez Perez , Dirk Werner

We consider the energy representation for the gauge group. The gauge group is the set of (C^{\infty})-mappings from a compact Riemannian manifold to a semi-simple compact Lie group. In this paper, we obtain irreducibility of the energy…

Mathematical Physics · Physics 2007-05-23 Yoshihito Shimada

We determine the computational complexity of the Hahn-Banach Extension Theorem. To do so, we investigate some basic connections between reverse mathematics and computable analysis. In particular, we use Weak Konig's Lemma within the…

Logic · Mathematics 2010-03-26 Guido Gherardi , Alberto Marcone

We consider the least-deletion map on the Cantor space, namely the map that changes the first 1 in a binary sequence to 0, and construct product measures on $2^\mathbb{N}$ so that the corresponding Radon-Nikodym cocycles oscillate or…

Dynamical Systems · Mathematics 2024-09-17 Sasha Bell , Tasmin Chu , Owen Rodgers

Let $G/K$ be a Riemannian symmetric space of noncompact type, and let $\nu_{a_j}$, $j=1,...,r$ be some orbital measures on $G$ (see the definition below). The aim of this paper is to study the $L^{2}$-regularity (resp. $C^k$-smoothness) of…

Representation Theory · Mathematics 2021-07-27 Boudjemaa Anchouche

We study measurable spaces equipped with a $\sigma$-ideal of negligible sets. We find conditions under which they admit a localizable locally determined version -- a kind of fiber space that describes locally their directions -- defined by…

Classical Analysis and ODEs · Mathematics 2021-05-25 Philippe Bouafia , Thierry De Pauw

Although there is a somewhat standard formalization of computability on countable sets given by Turing machines, the same cannot be said about uncountable sets. Among the approaches to define computability in these sets, order-theoretic…

Logic in Computer Science · Computer Science 2022-09-07 Pedro Hack , Daniel A. Braun , Sebastian Gottwald

In this paper we develop general techniques for classes of computable real numbers generated by subsets of total computable (recursive functions) with special restrictions on basic operations in order to investigate the following problems:…

Logic · Mathematics 2020-11-18 M. V. Korovina , O. V. Kudinov

We study computably enumerable equivalence relations (ceers) on N and unravel a rich structural theory for a strong notion of reducibility among ceers.

Logic · Mathematics 2010-12-07 Su Gao , Peter Gerdes

We begin to study classical dimension theory from the computable analysis (TTE) point of view. For computable metric spaces, several effectivisations of zero-dimensionality are shown to be equivalent. The part of this characterisation that…

Logic · Mathematics 2015-07-01 Robert Kenny

We derive computationally tractable methods to select a small subset of experiment settings from a large pool of given design points. The primary focus is on linear regression models, while the technique extends to generalized linear models…

Machine Learning · Statistics 2017-12-21 Yining Wang , Adams Wei Yu , Aarti Singh

We classify the finite dimensional irreducible representations of rectangular finite $W$-algebras, i.e., the finite $W$-algebras $U(\mathfrak{g}, e)$ where $\mathfrak{g}$ is a symplectic or orthogonal Lie algebra and $e \in \mathfrak{g}$ is…

Representation Theory · Mathematics 2010-03-11 Jonathan Brown

This article continues the study of computable elementary topology started by the author and T. Grubba in 2009 and extends the author's 2010 study of axioms of computable separation. Several computable T3- and Tychonoff separation axioms…

Logic · Mathematics 2015-07-01 Klaus Weihrauch

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

In a previous paper, we provided a formal definition for the concept of computational irreducibility (CIR), i.e. the fact for a function f from N to N that it is impossible to compute f(n) without following approximately the same path than…

Computational Complexity · Computer Science 2013-10-15 Herve Zwirn

We give a number of formal proofs of theorems from the field of computable analysis. Many of our results specify executable algorithms that work on infinite inputs by means of operating on finite approximations and are proven correct in the…

Logic in Computer Science · Computer Science 2023-06-22 Florian Steinberg , Laurent Thery , Holger Thies

Understanding internal representations of neural models is a core interest of mechanistic interpretability. Due to its large dimensionality, the representation space can encode various aspects about inputs. To what extent are different…

Machine Learning · Computer Science 2026-05-15 Xinting Huang , Michael Hahn

We compare three notions of effectiveness on uncountable structures. The first notion is that of a $\real$-computable structure, based on a model of computation proposed by Blum, Shub, and Smale, which uses full-precision real arithmetic.…

Logic · Mathematics 2008-09-01 Wesley Calvert