Universal objects in quasiconstructs
Rother, R.
Commentationes Mathematicae Universitatis Carolinae, Tome 41 (2000), p. 25-39 / Harvested from Czech Digital Mathematics Library
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The general theory of J'onsson-classes is generalized to strongly smooth quasiconstructs in such a way that it also allows the construction of universal categories. One example of the theory is the existence of a concrete universal category over every base category. Properties are given which are (under certain conditions) equivalent to the existence of homogeneous universal objects. Thereby, we disprove the existence of a homogeneous {\it C\/}-universal category. The notion of homogeneity is strengthened to extremal homogeneity. Extremally homogeneous universal objects, for which additionally every morphism between smaller subobjects is extendable to an endomorphism, are constructed in so called extremally smooth quasiconstructs.

Publié le : 2000-01-01
Classification:  18A40,  18B15 
@article{119138,
     author = {R. Rother},
     title = {Universal objects in quasiconstructs},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {41},
     year = {2000},
     pages = {25-39},
     zbl = {1034.18005},
     mrnumber = {1756924},
     language = {en},
     url = {http://dml.mathdoc.fr/item/119138}
}

Rother, R. Universal objects in quasiconstructs. Commentationes Mathematicae Universitatis Carolinae, Tome 41 (2000) pp. 25-39. http://gdmltest.u-ga.fr/item/119138/

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