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Related papers: The word problem for double categories

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We describe a mathematical framework for equational reasoning about infinite families of string diagrams which is amenable to computer automation. The framework is based on context-free families of string diagrams which we represent using…

Formal Languages and Automata Theory · Computer Science 2019-02-07 Vladimir Zamdzhiev

We study two modifications of the Post Correspondence Problem (PCP), namely 1) the bi-infinite version, where it is asked whether there exists a bi-infinite word such that two given morphisms agree on it, and 2) the conjugate version, where…

Discrete Mathematics · Computer Science 2022-09-16 Olivier Finkel , Vesa Halava , Tero Harju , Esa Sahla

String diagrams provide an intuitive language for expressing networks of interacting processes graphically. A discrete representation of string diagrams, called string graphs, allows for mechanised equational reasoning by double-pushout…

Logic in Computer Science · Computer Science 2015-10-14 Aleks Kissinger , Vladimir Zamdzhiev

The Kraft inequality gives a necessary and sufficient condition for the existence of a single channel prefix-free code. However, the multichannel Kraft inequality does not imply the existence of a multichannel prefix-free code in general.…

Information Theory · Computer Science 2019-04-30 Hoover H. F. Yin , Ka Hei Ng , Yu Ting Shing , Russell W. F. Lai , Xishi Wang

We examine the use of classes to formulate several categorical notions. This leads to two proposals: an explicit structure for working with subobjects, and a hierarchy of $k$-classes. We apply the latter to both ordinary and higher…

Category Theory · Mathematics 2018-07-27 Paul Blain Levy

We show that the Word Problem in finitely generated subgroups of $\textsf{GL}_d(\mathbb{Z})$ can be solved in linear average-case complexity. This is done under the bit-complexity model, which accounts for the fact that large integers are…

Group Theory · Mathematics 2025-09-17 Frédérique Bassino , Cyril Nicaud , Pascal Weil

A popular graphical calculus for monoidal categories makes computations tactile and intuitive. Complicated diagram chases can be expressed in a few pictures and discovered by playing with a shoelace. Joyal and Street's proof of the…

Category Theory · Mathematics 2018-03-05 David Jaz Myers

Under categorial grammars that have powerful rules like composition, a simple n-word sentence can have exponentially many parses. Generating all parses is inefficient and obscures whatever true semantic ambiguities are in the input. This…

cmp-lg · Computer Science 2008-02-03 Jason Eisner

In this paper we redevelop the foundations of the category theory of quasi-categories (also called infinity-categories) using 2-category theory. We show that Joyal's strict 2-category of quasi-categories admits certain weak 2-limits, among…

Category Theory · Mathematics 2015-06-18 Emily Riehl , Dominic Verity

The question of whether all words in two real positive definite letters have only positive eigenvalues is addressed and settled (negatively). This question was raised some time ago in connection with a long-standing problem in theoretical…

Operator Algebras · Mathematics 2007-05-23 Christopher J Hillar , Charles R Johnson

One of the most interesting questions about a group is if its word problem can be solved and how. The word problem in the braid group is of particular interest to topologists, algebraists and geometers, and is the target of intensive…

Group Theory · Mathematics 2007-05-23 David Garber , Shmuel Kaplan , Mina Teicher

This article continues our study on simple bilevel and simple MPEC problems. In this article we focus on developing algorithms. We show how using the idea of a gap function one can represent a simple MPEC as a simple bilevel problem with…

Optimization and Control · Mathematics 2019-12-16 Stephan Dempe , Nguyen Dinh , Joydeep Dutta , Tanushree Pandit

This paper presents a new model for word sense disambiguation formulated in terms of evolutionary game theory, where each word to be disambiguated is represented as a node on a graph whose edges represent word relations and senses are…

Artificial Intelligence · Computer Science 2017-04-07 Rocco Tripodi , Marcello Pelillo

We use double categories to obtain a single theorem characterizing certain exponentiable morphisms of small categories, topological spaces, locales, and posets.

Category Theory · Mathematics 2012-04-25 Susan Niefield

Understanding of free-format multi-step arithmetic word problems with extraneous information is discussed. A model including a full set of general skills necessary for understanding such problems was developed and computer implemented. The…

General Mathematics · Mathematics 2007-05-23 Yefim Bakman

We characterize virtual double categories of enriched categories, functors, and profunctors by introducing a new notion of double-categorical colimits. Our characterization is strict in the sense that it is up to equivalence between virtual…

Category Theory · Mathematics 2026-04-07 Yuto Kawase

We study the equality problem for infinite words obtained by iterating morphisms. In particular, we give a practical algorithm to decide whether or not two words generated by primitive morphisms are equal.

Formal Languages and Automata Theory · Computer Science 2009-04-16 Juha Honkala

This paper explores the use of 2-categorical technology for describing and reasoning about complex quantum procedures. We give syntactic definitions of a family of complementary measurements, and of quantum key distribution, and show that…

Logic in Computer Science · Computer Science 2014-12-31 Krzysztof Bar , Jamie Vicary

In this paper we obtain an algorithm towards solving the two-dimensional moment problem. This algorithm gives the necessary and sufficient conditions for the solvability of the moment problem. It is shown that all solutions of the moment…

Functional Analysis · Mathematics 2010-09-27 Sergey M. Zagorodnyuk

Word translation is a problem in machine translation that seeks to build models that recover word level correspondence between languages. Recent approaches to this problem have shown that word translation models can learned with very small…

Computation and Language · Computer Science 2019-12-24 Blaine Cole