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Pro-Categories and Multiadjoint Functors

Published online by Cambridge University Press:  20 November 2018

Walter Tholen*
Affiliation:
York University, Downsview, Ontario
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For a functor G:𝒜𝔛 and a class 𝔇 of small categories containing the terminal category 1 we form the extension

and call G right 𝔇-pro-adjoint if and only if Pro (𝔇, G) is right adjoint. Here Pro (𝔇, 𝒜) is the completion of 𝒜with respect to 𝔇; it coincides with the usual pro-category of 𝒜 in case 𝔇 = directed sets. For this 𝔇 a full embedding Gis dense in the sense of Mardešić [11] if and only if it is right 𝔇-pro-adjoint in the above sense; this has been proved recently by Stramaccia [15]. The most important example is the embedding of the homotopy category of pointed CW-complexes into the homotopy category of pointed topological spaces (cf. [2]).

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1984

References

1. Börger, R. and Tholen, W., Abschwächungen des Adjunktionsbegriffs, Manuscripta Math. 79 (1976), 1945.Google Scholar
2. Borsuk, K. and Dydak, J., What is the theory of shape?, Bull. Austral. Math. Soc. 22 (1980), 161198.Google Scholar
3. Diers, Y., Familles universelles de morphismes, Ann. Soc. Sci. Bruxelles 93 (1979), 175195.Google Scholar
4. Diers, Y., Multimonads and multimonadic categories, J. Pure Appl. Algebra 17 (1980), 153170.Google Scholar
5. Giuli, E., Relations between reflective subcategories and shape theory, Glasnik Mat. 16 (1981), 205210.Google Scholar
6. Grothendieck, A. and Verdier, J. L., Prefaisceaux, in: Théorie des topos et cohomologie étale des schémas (Séminaire de Géométrie Algébrique du Bois Marie 1963/64, SGA 4), Lecture Notes in Math. 269 (Springer, Berlin, 1972), 1217.Google Scholar
7. Guitart, R. and Lair, C., Calcul syntaxique des modèles et calcul de formules internes, Diagrammes 4 (1980), 1106.Google Scholar
8. Herrlich, H., Initial completions, Math. Z. 750 (1976), 101110.Google Scholar
9. Johnstone, P. and Joyal, A., Continuous categories and exponentiable toposes, J. Pure Appl. Algebra 25 (1982), 255296.Google Scholar
10. Lambek, J., Completions of categories, Lecture Notes in Math. 24 (Springer, Berlin, 1966).CrossRefGoogle Scholar
11. Mardešić, S., Foundations of shape theory, University of Kentucky, (1978).Google Scholar
12. Salicrup, G., Local monocoreflectivity in topological categories, Lecture Notes in Math. 975 (Springer, Berlin, 1982), 293309.Google Scholar
13. Salicrup, G., Multiepireflective subcategories, Topology Appl. 13 (1982), 191200.Google Scholar
14. Stauffer, H. B., On an embedding of a category into its completion, J. Indian Math. Soc. 42 (1978), 263266.Google Scholar
15. Stramaccia, L., Reflective subcategories and dense subcategories, Rend. Sem. Mat. Univ. Padova 67 (1982), 191198.Google Scholar
16. Tholen, W., Semi-topological functors I, J. Pure Appl. Algebra 75 (1979), 5373.Google Scholar
17. Tholen, W., MacNeille completion of concrete categories with local properties, Comment. Math. Univ St. Pauli 28 (1978), 179202.Google Scholar
18. Tholen, W., Completions of categories and shape theory, in: Proceedings of the Fifth Prague Topological Symposium 1981 (Heldermann-Verlag, Berlin, 1983), 593607.Google Scholar
19. Weberpals, H., Über einen Satz von Gabriel zur Charakterisierung reguldrer Colimites, Math. Z. 767 (1978), 4767.Google Scholar