Closure operators and projections on involution posets
نویسندگان
چکیده
منابع مشابه
Pseudocomplements of closure operators on posets
Some recent results provide su,cient conditions for complete lattices of closure operators on complete lattices, ordered pointwise, to be pseudocomplemented. This paper gives results of pseudocomplementation in the more general setting of closure operators on mere posets. The following result is 0rst proved: closure operators on a meet-continuous meet-semilattice form a pseudocomplemented compl...
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Torsion theories are here extended to categories equipped with an ideal of 'null morphisms', or equivalently a full subcategory of 'null objects'. Instances of this extension include closure operators viewed as generalised torsion theories in a 'category of pairs', and factorization systems viewed as torsion theories in a category of morphisms. The first point has essentially been treated in [15].
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ژورنال
عنوان ژورنال: Journal of the Australian Mathematical Society
سال: 1974
ISSN: 0004-9735
DOI: 10.1017/s1446788700029141