Abstract
In this paper, we generalize the notions of polymorphisms and invariant relations to arbitrary categories. This leads us to a Galois connection that coincides with the classical case from universal algebra if the underlying category is the category of sets, but remains applicable no matter how the category is changed. In analogy to the situation in the classical case, we characterize the Galois closed classes by local closures of clones of operations and local closures of what we will introduce as clones of (generalized) relations. Since the approach is built on purely category-theoretic properties, we will also discuss the dualization of our notions.
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Bodnartchuk, V.G., Kaluznin, L.A., Kotov, V.N., Romov, B.A.: Galois theory for Post algebras, 1–2. Kibernitika (Kiev) 3, 1–10 (1969)
Börner, F.: Operationen auf Relationen. PhD thesis, Universität Leipzig (1988)
Couceiro, M.: Galois connections for generalized functions and relational constraints. In: Contributions to General Algebra, vol. 16, pp. 31–54. Heyn, Klagenfurt (2005)
Csákány B.: Completeness in coalgebras. Acta Sci. Math. 48, 75–84 (1985)
Dolinka I.: On Kleene algebras of ternary co-relations. Acta Cybernet. 14, 583–595 (2000)
Geiger D.: Closed systems of functions and predicates. Pacific J. Math. 27, 95–100 (1968)
Hyland, M., Power, J.: The category theoretic understanding of universal algebra: Lawvere theories and monads. In: Computation, Meaning, and Logic: Articles Dedicated to Gordon Plotkin. Electron. Notes Theor. Comput. Sci., vol. 172, pp. 437–458. Elsevier, Amsterdam (2007)
Kerkhoff, S.: A general duality theory for clones. PhD thesis, Technische Universität Dresden (2011)
Krasner, M.: Remarque au sujet d’ “Une généralisation de la notion de corps” (Journ. de Math., 1938, p. 367–385). J. Math. Pures Appl. 18, 417–418 (1939) (French)
Lawvere, W.F.: Functorial Semantics of Algebraic Theories and Some Algebraic Problems in the context of Functorial Semantics of Algebraic Theories. PhD thesis, Columbia University (1963)
Markl, M.: Operads and PROPs. In: Handbook of algebra. Vol. 5, pp. 87–140. Handb. Algebr, 5, Elsevier/North-Holland, Amsterdam (2008)
Mašulović D.: Equivalence co-relations and co-congruences of co-algebras. Novi Sad J. Math. 31, 33–38 (2001)
Mašulović D.: On dualizing clones as Lawvere theories. Internat. J. Algebra Comput. 16, 675–687 (2006)
Mašulović D., Pöschel R.: Rosenberg co-relations. Ivo G. Rosenberg’s 65th birthday, Mult.-Valued Log 5, 229–238 (2000)
Mašulović, D., Rössiger, M.: Algebras of co-relations on a finite set. In: Contributions to General Algebra (Velké Karlovice, 1999, Dresden, 2000), vol. 13, pp. 219–232. Heyn, Klagenfurt (2001)
McKenzie, R.N., McNulty, G.F., Taylor W.: Algebras, Lattices, Varieties, vol. 1. Wadsworth & Brooks/Cole, Monterey (1987)
Pöschel, R., Kalužnin, L.A.: Funktionen- und Relationenalgebren. Deutscher Verl. der Wiss., Berlin (1979)
Pöschel, R.: Concrete representation of algebraic structures and a general Galois theory. In: Contributions to General Algebra (Klagenfurt, 1978), pp. 249–272. Heyn, Klagenfurt (1979)
Pöschel, R.: A general Galois theory for operations and relations and concrete characterization of related algebraic structures. Report 1980, vol 1. Akademie der Wissenschaften der DDR Institut für Mathematik, Berlin (1980)
Pöschel R., Rössiger M.: A general Galois theory for cofunctions and corelations. Algebra Universalis 43, 331–345 (2000)
Post, E.L.: The Two-Valued Iterative Systems of Mathematical Logic. Annals of Mathematics Studies, no. 5. Princeton University Press, Princeton (1941)
Priestley H.A.: Representation of distributive lattices by means of ordered Stone spaces. Bull. London Math. Soc. 2, 186–190 (1972)
Rosenberg, I.G.: A classification of universal algebras by infinitary relations. Algebra Universalis 1, 350–354 (1971/72)
Rosenberg, I.G.: Galois theory for partial algebras. In: Universal Algebra and Lattice Theory (Puebla, 1982). Lecture Notes in Mathematics, vol. 1004, pp. 257–272. Springer, Berlin (1983)
Rößiger, M.: A unified general Galois theory. Ivo G. Rosenberg’s 65th birthday, Mult.-Valued Log. 5, 239–258 (2000)
Szabó L.: Concrete representation of related structures of universal algebras, I. Acta Sci. Math. (Szeged) 40, 175–184 (1978)
Szendrei, Á.: Clones in Universal Algebra. Séminaire de Mathématiques Supérieures Seminar on Higher Mathematics], vol. 99. Presses de l’Université de Montréal, Montreal (1986)
Taylor, W.: The Clone of a Topological Space. Research and Exposition in Mathematics, vol. 13. Heldermann, Berlin (1986)
Taylor, W.: Abstract clone theory. In: Algebras and Orders (Montreal, 1991). NATO Adv. Sci. Inst. Ser. C Math. Phys. Sci., vol. 389, pp. 507–530. Kluwer, Dordrecht (1993)
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Kerkhoff, S. A general Galois theory for operations and relations in arbitrary categories. Algebra Univers. 68, 325–352 (2012). https://doi.org/10.1007/s00012-012-0209-9
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DOI: https://doi.org/10.1007/s00012-012-0209-9