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81.
In this paper,the category of L-FTOP and the relations with the categories of TOP,Lα-FTOP are discussed. 相似文献
82.
黄文林 《浙江大学学报(理学版)》1959,46(6):651-655
83.
This work is a complement to the authors earlier papers, where it is shown that a functor category
inherits from
such properties as amalgamation, transferability and congruence extension if
has either products or certain pushouts. A general scheme is given for constructing counter-examples which show that the latter condition on
is essential. In particular, it is shown that the functor categories
,
,
(
resp.) do not satisfy the amalgamation (congruence extension resp.) property in general. Moreover, one class of categories is described, where the condition of the existence of certain pushouts is not only sufficient, but also necessary for
to preserve the considered properties of
.Mathematics Subject Classifications (2000) 18A25, 18A32, 18B99, 08B26.Dali Zangurashvili: The support rendered by INTAS Grant 97 31961 is gratefully acknowledged. 相似文献
84.
85.
We introduce a notion of a subtractive category. It generalizes the notion of a pointed subtractive variety of universal algebras in the sense of A. Ursini. Subtractive categories are closely related to Mal’tsev and additive categories: (i) a category C with finite limits is a Mal’tsev category if and only if for every object X in C the category Pt(X)=((X,1X)↓(C↓X)) of “points over X” is subtractive; (ii) a pointed category C with finite limits is additive if and only if C is subtractive and half-additive.Mathematics Subject Classifications (2000) 18C99, 18E05, 08B05. 相似文献
86.
Nilson C. Bernardes Jr. 《Proceedings of the American Mathematical Society》2005,133(12):3473-3483
Given a metrizable compact topological -manifold with boundary and a metric compatible with the topology of , we prove that ``most' continuous functions are non-sensitive at ``most' points of but are sensitive at every point of an infinite set which is dense in the set of all periodic points of . We also establish some results concerning sets of periodic points and non-wandering points.
87.
Given an algebraic theory
whose category of models is semi-abelian, we study the category
of topological models of
and generalize to it most classical results on topological groups. In particular,
is homological, which includes Barr regularity and forces the Mal'cev property. Every open subalgebra is closed and every quotient map is open. We devote special attention to the Hausdorff, compact, locally compact, connected, totally disconnected and profinite
-algebras. 相似文献
88.
Esther Beneish 《Proceedings of the American Mathematical Society》2006,134(7):1869-1873
Let be a prime greater than , and let be the semi-direct product of a group of order by a cyclic group of order , which acts faithfully on . Let be the localization of at . We show that the Krull-Schmidt Theorem fails for the category of invertible -lattices.
89.
Fang LI Gong Xiang LIU 《数学学报(英文版)》2006,22(4):1027-1046
There are at least two kinds of generalization of Hopf algebra, i.e. pre-Hopf algebra and weak Hopf algebra. Correspondingly, we have two kinds of generalized bialgebras, almost bialgebra and weak bialgebra. Let L = (L, ×, I, a, l, r) be a tensor category. By giving up I, l, r and keeping ×, a in L, the first author got so-called pre-tensor category L = (L, ×, a) and used it to characterize almost bialgebra and pre-Hopf algebra in Comm. in Algebra, 32(2): 397-441 (2004). Our aim in this paper is to generalize tensor category L = (L, ×, I, a, l, r) by weakening the natural isomorphisms l, r, i.e. exchanging the natural isomorphism ll^-1 = rr^-1 = id into regular natural transformations lll= l, rrr = r with some other conditions and get so-called weak tensor category so as to characterize weak bialgebra and weak Hopf algebra. The relations between these generalized (bialgebras) Hopf algebras and two kinds generalized tensor categories will be described by using of diagrams. Moreover, some related concepts and properties about weak tensor category will be discussed. 相似文献
90.
Tetsuya Sato 《Journal of Pure and Applied Algebra》2018,222(10):2888-2896
We show that the Giry monad is not strong with respect to the canonical symmetric monoidal closed structure on the category Meas of all measurable spaces and measurable functions. 相似文献