منابع مشابه
2 00 4 Isomorphic Implication ∗
We study the isomorphic implication problem for Boolean constraints. We show that this is a natural analog of the subgraph isomorphism problem. We prove that, depending on the set of constraints, this problem is in P, NP-complete, or NP-hard, coNP-hard, and in P || . We show how to extend the NP-hardness and coNP-hardness to P || -hardness for some cases, and conjecture that this can be done in...
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We first provide an example of a ring R such that all possible 2 × 2 structural matrix rings over R are isomorphic. However, we prove that the underlying graphs of any two isomorphic structural matrix rings over a semiprime Noetherian ring are isomorphic, i.e. the underlying Boolean matrix B of a structural matrix ring M(B,R) over a semiprime Noetherian ring R can be recovered, contrary to the ...
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Dye, [Ann. of Math. (2) 61 (1955), 73–89] proved that the discrete unitary group in a factor determines the algebraic type of the factor. Afterwards, for a large class of simple unital C∗-algebras, Al-Rawashdeh, Booth and Giordano [J. Funct. Anal. 262 (2012), 4711–4730] proved that the algebras are ∗-isomorphic if and only if their unitary groups are isomorphic as abstract groups. In this paper...
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It is examined in several papers when is it true the isomorphism of two cylindric set algebras is a base-isomorphism. Problem 1. For which M ∈ CAα it is true that if for i = 0 and i = 1 Di ∈ Caα, f i : M→Di is an isomorphisms, and base Di = Vi imply that there exists a bijection g : V0 → V1 such that g = f1 ◦ f −1 0 (for notations and notions see [3] and [5]). By the Löwenheim-Skolem theorem th...
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ژورنال
عنوان ژورنال: Theory of Computing Systems
سال: 2007
ISSN: 1432-4350,1433-0490
DOI: 10.1007/s00224-007-9038-1