Results 1 to 10 of about 202 (44)
A construction of cylindric and polyadic algebras from atomic relation algebras [PDF]
Algebra universalis, 2012 The purpose of this paper is to present a construction that does preserve and reflect representability in higher dimensions than 3. Given a simple atomic relation algebra \({\mathcal A}\) and a finite \(n\geq 3\), the author constructs effectively an atomic \(n\)-dimensional polyadic equality-type algebra \({\mathcal P}\) that for any signature \(L ...
openaire +3 more sources
Bulletin of the Section of Logic, 2021 Fix a finite ordinal \(n\geq 3\) and let \(\alpha\) be an arbitrary ordinal. Let \(\mathsf{CA}_n\) denote the class of cylindric algebras of dimension \(n\) and \(\sf RA\) denote the class of relation algebras.
Tarek Sayed Ahmed
doaj +1 more source
Some variants of Vaught’s conjecture from the perspective of algebraic logic [PDF]
, 2012 Vaught’s Conjecture states that if T is a complete first order theory in a countable language such that T has uncountably many pairwise non-isomorphic countably infinite models, then T has 2^ℵ_0 many pairwise non-isomorphic countably infinite models ...
Sziráki, Dorottya, Sági, Gábor
core +1 more source
, 2018 This essay is about how the notion of “structure” in ontic structuralism might be made precise. More specifically, my aim is to make precise the idea that the structure of the world is (somehow) given by the relations inhering in the world, in such a way
Dewar, Neil
core +2 more sources
, 2013 This chapter surveys the development in the theory of polyadic algebras in the last ...
Sági, Gábor
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A non-standard analysis of a cultural icon: The case of Paul Halmos [PDF]
, 2016 We examine Paul Halmos' comments on category theory, Dedekind cuts, devil worship, logic, and Robinson's infinitesimals. Halmos' scepticism about category theory derives from his philosophical position of naive set-theoretic realism.
Blaszczyk, Piotr +6 more
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Connections between Relation Algebras and Cylindric Algebras [PDF]
, 2015 . We give an informal description of a recursive representability-preserving reduction of relation algebras to cylindric algebras.
A. Tarski +7 more
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Undecidable relativizations of algebras of relations. [PDF]
, 1999 In this paper we show that relativized versions of relation set algebras and cylindric set algebras have undecidable equational theories if we include coordinatewise versions of the counting operations into the similarity type.
Andréka +13 more
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Neat embeddings as adjoint situations
, 2013 We view the neat reduct operator as a functor that lessens dimensions from CA_{\alpha+\omega} to CA_{\alpha} for infinite ordinals \alpha. We show that this functor has no right adjoint. Conversely for polyadic algebras, and several reducts thereof, like
Ahmed, Tarek Sayed
core +1 more source
Complexity of equational theory of relational algebras with standard projection elements [PDF]
, 2015 The class \(\mathsf{TPA}\) of t rue p airing a lgebras is defined to be the class of relation algebras expanded with concrete set theoretical projection functions.
A Tarski +28 more
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