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Related papers: Blow up and Blur constructions in Algebraic Logic

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We give a simpler proof of a result of Hodkinson in the context of a blow and blur up construction argueing that the idea at heart is similar to that adopted by Andr\'eka et all \cite{sayed}. The idea is to blow up a finite structure,…

Logic · Mathematics 2013-05-21 Tarek Sayed Ahmed

In this paper we give an alternative construction using Monk like algebras that are binary generated to show that the class of strongly representable atom structures is not elementary. The atom structures of such algebras are cylindric…

Logic · Mathematics 2013-07-17 Tarek Sayed Ahmed , Mohammed Khaled

This paper is a survey of recent results and methods in (Tarskian) algebraic logic. We focus on cylindric algebras. Fix 2<n<\omega. Rainbow constructions are used to solve problems on classes consisting of algebras having a neat embedding…

Logic · Mathematics 2015-02-27 Tarek Sayed Ahmed

Using model theoretic techniques that proved that the class of $n$ neat reducts of $m$ dimensional cylindric algebras, $\Nr_n\CA_m$, is not elementary, we prove the same result for $\Ra\CA_k$, $k\geq 5$, and we show that $\Ra\CA_k\subset…

Logic · Mathematics 2013-05-24 Tarek Sayed Ahmed

We use Monk like algebras to give a new proof that the classes of strongly representable relation algebras and finite dimensional cylindric algebras of dimension >2 are not elementary. Our construction is based on relation algebras have…

Logic · Mathematics 2013-05-21 Tarek Sayed Ahmed

We deal with various splitting methods in algebraic logic. The word `splitting' refers to splitting some of the atoms in a given relation or cylindric algebra each into one or more subatoms obtaining a bigger algebra, where the number of…

Logic · Mathematics 2015-03-10 Tarek Sayed Ahmed

Using constructions of Hirsch and Hodkinson, we show that the class of strongly atom structures for various cylindric-like algebras is not elementary. This applies to diagonal free reducts and polyadic algebras with and without equality.…

Logic · Mathematics 2013-04-22 Tarek Sayed Ahmed , Mohamed Khalifa

(1) Let 1\leq k\leq \omega. Call an atom structure \alpha weakly k neat representable, the term algebra is in \RCA_n\cap \Nr_n\CA_{n+k}, but the complex algebra is not representable. Call an atom structure neat if there is an atomic algebra…

Logic · Mathematics 2013-05-23 Tarek Sayed Ahmed

The objective of this paper is to determine the finite dimensional, indecomposable representations of the algebra that is generated by two complex structures over the real numbers. Since the generators satisfy relations that are similar to…

Representation Theory · Mathematics 2008-04-24 Steven Gindi

We characterize completey (give a necessary and suffcient condition using special neat embeddings)for a relation algebra to belong to the amalgamation, strong amalgamation, and superamalgamation base of the class of representable algebras.…

Logic · Mathematics 2013-04-03 Tarek Sayed Ahmed

We take a long magical tour in algebraic logic, starting from classical results on neat embeddings due to Henkin, Monk and Tarski, all the way to recent results in algebraic logic using so--called rainbow constructions invented by Hirsch…

Logic · Mathematics 2015-08-25 Tarek Sayed Ahmed

We prove that the Weihrauch lattice can be transformed into a Brouwer algebra by the consecutive application of two closure operators in the appropriate order: first completion and then parallelization. The closure operator of completion is…

Logic · Mathematics 2021-07-01 Vasco Brattka , Guido Gherardi

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

The notion of a complete Boolean algebra, although completely legitimate in constructive mathematics, fails to capture some natural structures such as the lattice of subsets of a given set. Sambin's notion of an overlap algebra, although…

Logic in Computer Science · Computer Science 2023-06-22 Francesco Ciraulo , Michele Contente

In this paper we define infinite-dimensional algebra and its representation, whose basis is naturally identified with semi-infinite configurations of the square ladder model. We also extrapolate the ideas for the cyclic 3-leg triangular…

Combinatorics · Mathematics 2022-06-14 Valerii Sopin

A relation algebra is called measurable when its identity is the sum of measurable atoms, and an atom is called measurable if its square is the sum of functional elements. In this paper we show that atomic measurable relation algebras have…

Logic · Mathematics 2025-02-12 S. Givant , H. Andréka

We introduce the notion of the full quiver of a representation of an algebra, which is a cover of the (classical) quiver, but which captures properties of the representation itself. Gluing of vertices and of arrows enables one to study…

Rings and Algebras · Mathematics 2017-12-05 Alexei Belov-Kanel , Louis H. Rowen , Uzi Vishne

We generalize the notion of Monk's schema in such a way to integrate finite dimensions. This allows us to lift a plathora of deep results proved for finite dimensions to the infinite dimensional case, like the solution to problem 2.12 in…

Logic · Mathematics 2013-09-04 Tarek Sayed Ahmed

We give a geometric interpretation of cluster varieties in terms of blowups of toric varieties. This enables us to provide, among other results, an elementary geometric proof of the Laurent phenomenon for cluster algebras (of geometric…

Algebraic Geometry · Mathematics 2014-04-16 Mark Gross , Paul Hacking , Sean Keel

We introduce the blockwise gluing construction. This describes residuated integral chains which can be decomposed into (possibly) partial algebras, stacked one on top of the other, and such that elements in a certain component multiply in…

Logic · Mathematics 2025-12-22 Valeria Giustarini , Sara Ugolini
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