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pro vyhledávání: '"Tarek Sayed Ahmed"'
Lifting Results for Finite Dimensions to the Transfinite in Systems of Varieties Using Ultraproducts
Autor:
Tarek Sayed Ahmed
Publikováno v:
Bulletin of the Section of Logic, Vol 53, Iss 2, Pp 145-154 (2024)
We redefine a system of varieties definable by a schema of equations to include finite dimensions. Then we present a technique using ultraproducts enabling one to lift results proved for every finite dimension to the transfinite. Let \(\bf Ord\) deno
Externí odkaz:
https://doaj.org/article/ef53230790c3494f97e69239419526b2
Autor:
Tarek Sayed Ahmed
Publikováno v:
Bulletin of the Section of Logic, Vol 51, Iss 3, Pp 411-453 (2022)
Let \(2
Externí odkaz:
https://doaj.org/article/01a199a43a0f45a6a0ee682adc55c11c
Autor:
Tarek Sayed Ahmed
Publikováno v:
Bulletin of the Section of Logic, Vol 50, Iss 4, Pp 465-511 (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. Let \(\mathbf{PA}_{\alpha}(\mathsf{PEA}
Externí odkaz:
https://doaj.org/article/6401f276a5fc4826bff340e487283973
Autor:
Tarek Sayed Ahmed
Publikováno v:
Bulletin of the Section of Logic, Vol 50, Iss 3, Pp 249-287 (2021)
Fix \(2 < n < \omega\). Let \(L_n\) denote first order logic restricted to the first n variables. Using the machinery of algebraic logic, positive and negative results on omitting types are obtained for \(L_n\) and for infinitary variants and extensi
Externí odkaz:
https://doaj.org/article/8d320481a91e45349278b9c23c68ed3c
Autor:
Tarek Sayed Ahmed
Publikováno v:
Journal of the Egyptian Mathematical Society, Vol 19, Iss 1, Pp 4-16 (2011)
The notion of neat reducts is an old venerable notion in cylindric algebra theory invented by Henkin. This notion is regaining momentum. In this paper we explain why. This notion is discussed in connection to the algebraic notions of representability
Externí odkaz:
https://doaj.org/article/76b14a8fa5cc409c9167595084d0732d
Notions of representability for cylindric algebras: some algebras are more representable than others
Autor:
Tarek Sayed Ahmed
Publikováno v:
Periodica Mathematica Hungarica. 86:343-377
The theory of cylindric algebras was introduced by Tarski in the fifties of the twentieth century, and its intensive study was further pursued by pioneers such as Henkin and Monk and, by the Hungarian mathematicians Andréka, Németi and Sain, and ma
Autor:
Omar Ossman, Tarek Sayed Ahmed
Publikováno v:
JP Journal of Algebra, Number Theory and Applications. :217-233
Autor:
Tarek Sayed Ahmed
Publikováno v:
Journal of Applied Non-Classical Logics. 30:223-271
Fix 2 < n < ω and let C A n denote the class of cylindric algebras of dimension n. Roughly, C A n is the algebraic counterpart of the proof theory of first-order logic restricted to the first n var...
Autor:
Tarek Sayed Ahmed
Publikováno v:
JP Journal of Algebra, Number Theory and Applications. 47:99-119
Autor:
Tarek Sayed Ahmed
Publikováno v:
International Journal of Algebra. 14:43-137