Results 301 to 310 of about 213,067 (334)
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Triple Covers in Algebraic Geometry
American Journal of Mathematics, 1985The aim of the paper under review is to develop a theory of triple covers in algebraic geometry. One of the most important general result obtained says that a triple cover \(X\to Y\) (with X and Y irreducible varieties over an algebraically closed field) is determined by a rank-two vector bundle E and a map \(S^ 3E\to \bigwedge^ 2E\), and conversely ...
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On Covers of Perfect Lie Algebras
Algebra Colloquium, 2011A Lie algebra is said to be perfect when it coincides with its derived subalgebra. The paper is devoted to give a complete structure of covers of perfect Lie algebras. Also, similar to a result of Alperin and Gorenstein (1966) in group theory, it is shown that every automorphism of a finite dimensional perfect Lie algebra may be lifted to an ...
Salemkar, Ali Reza +2 more
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Effect Algebras Which Can Be Covered by MV-Algebras
International Journal of Theoretical Physics, 2002Effect algebras are partial abelian monoids with a sort of negation operation: they yield a generalization of various kinds of structures currently used in the algebraic treatment of operator algebras, including Chang's MV algebras. The main result of this paper gives added evidence to the intuition that MV algebras stand to effect algebras as Boolean ...
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2004
Let p be a prime number and let G be a finite group. The subgroup p(G) ⊂ G is defined as the group generated by all elements in G having as order a power of p. Equivalent definitions of p(G) are: (i) p(G) is the smallest normal subgroup such that the factor group G/p(G) has no elements with order p.
Jean Fresnel, Marius van der Put
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Let p be a prime number and let G be a finite group. The subgroup p(G) ⊂ G is defined as the group generated by all elements in G having as order a power of p. Equivalent definitions of p(G) are: (i) p(G) is the smallest normal subgroup such that the factor group G/p(G) has no elements with order p.
Jean Fresnel, Marius van der Put
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Koszul algebras and finite Galois coverings
Science in China Series A: Mathematics, 2009zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Zhao, Deke, Han, Yang
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Irredundant Coverings, Tolerances, and Related Algebras
2018This chapter deals with rough approximations defined by tolerance relations that represent similarities between the elements of a given universe of discourse. We consider especially tolerances induced by irredundant coverings of the universe U. This is natural in view of Pawlak’s original theory of rough sets defined by equivalence relations: any ...
Järvinen J., Radeleczki, S.
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Descent varieties for algebraic covers
Journal für die reine und angewandte Mathematik (Crelles Journal), 2004The paper is dedicated to descent varieties meaning the following. Given a cover \(f:X\to B\) over a field, produce a parameter space \(V\) for families of models of \(f\) satisfying the following versal property: each model of \(f\) is a fiber of the family, so it corresponds to points of \(V\).
Dèbes, Pierre +2 more
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Communications in Algebra, 1996
In dealing with the central extensions of a finite group G one finds that although covers need not be isomorphic, for each such H there exists a cover for which H is a. homomorphic image [1]. For finite dimensional Lie algebras, covers are isomorphic. We shall show that the second property also holds for Lie algebras.
Peggy Batten, Ernest Stitzinger
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In dealing with the central extensions of a finite group G one finds that although covers need not be isomorphic, for each such H there exists a cover for which H is a. homomorphic image [1]. For finite dimensional Lie algebras, covers are isomorphic. We shall show that the second property also holds for Lie algebras.
Peggy Batten, Ernest Stitzinger
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Algebraic Modelling of Covering Arrays
2017We introduce a novel technique to model and compute binary covering arrays, discrete combinatorial structures, based on a tuple-level modelling and using methods arising from linear algebra, commutative algebra and symbolic computation. Concrete instances of covering arrays for given parameters will arise as points in a generated variety of a system of
Bernhard Garn, Dimitris E. Simos
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Covering Spaces of Algebraic Groups
The American Mathematical Monthly, 1976(1976). Covering Spaces of Algebraic Groups. The American Mathematical Monthly: Vol. 83, No. 8, pp. 614-621.
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