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Kleene algebras are almost universal

Published online by Cambridge University Press:  17 April 2009

M. E. Adams
Affiliation:
State University of New York, New Paltz, New York 12561, U.S.A.
H. A. Priestley
Affiliation:
Mathematical Institute, 24/29 St. Giles, Oxford OX1 3LB, England.
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Abstract

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This paper studies endomorphism monoids of Kleene algebras. The main result is that these algebras form an almost universal variety k, from which it follows that for a given monoid M there is a proper class of non-isomorphic Kleene algebras with endomorphism monoid M+ (where M+ denotes the extension of M by a single element that is a right zero in M+). Kleene algebras form a subvariety of de Morgan algebras containing Boolean algebras. Previously it has been shown the latter are uniquely determined by their endomorphisms, while the former constitute a universal variety, containing, in particular, arbitrarily large finite rigid algebras. Non-trivial algebras in K always have non-trivial endomorphisms (so that universality of K is ruled out) and unlike the situation for de Morgan algebras the size of End(L) for a finite Kleene algebra L necessarily increases as |L| does. The paper concludes with results on endomorphism monoids of algebras in subvarieties of the variety of MS-algebras.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1986

References

[1]Adams, M. E., Koubek, V., and Sichler, J., “Homomorphisms and endomorphisms in varieties of pseudocomplemented distributive lattices (with applications to Heyting algebras)”, Trans. Amer. Math. Soc. 285 (1984), 5779.CrossRefGoogle Scholar
[2]Adams, M. E., Koubek, V., and Sichler, J., “Homomorphisms and endomorphisms of distributive lattices”, Houston J. Math. 11 (1985), 129145.Google Scholar
[3]Adams, M. E. and Priestley, H. A., “De Morgan algebras are universal”, (to appear).Google Scholar
[4]Balbes, R. and Dwinger, Ph., Distributive Lattices, (university of Missouri Press, Columbia, Missouri, 1974).Google Scholar
[5]Beazer, R., “On some small varieties of distributive Ockham algebras”, Glasgow Math. J. 25 (1984) 175181.CrossRefGoogle Scholar
[6]Berman, J., “Distributive lattices with and additional unary operationAequationes Math. 16 (1977), 165171.CrossRefGoogle Scholar
[7]Blyth, T. S. and Varlet, J. C., “On a common abstraction of de Morgan algebras and Stone algebras”, Proc. Roy. Soc. Edinburgh Sect.A 94 (1983), 301308.CrossRefGoogle Scholar
[8]Blyth, T. S. and Varlet, J. C., “Subvarieties of the class of MS-algebras”, Proc. Roy. Soc. Edinburgh Sect.A 95 (1983), 157169.CrossRefGoogle Scholar
[9]Clark, D. M. and Krauss, P. H., “On topological quasivarieties”, Acta Sci. Math. 47 (1984), 339.Google Scholar
[10]Cornish, W. H. and Fowler, P. R., “Coproducts of de Morgan algebras”, Bull. Austral. Math. Soc. 16 (1977), 113.CrossRefGoogle Scholar
[11]Cornish, W. H. and Fowler, P. R., “Coproducts of Kleene algebras”, J. Austral. Math. Soc. Ser. A 27 (1979), 209220.CrossRefGoogle Scholar
[12]Davey, B. A. and Duffus, D., “Exponentiation and duality”, in Ordered Sets (ed. Rival, I.), NATO Advanced Study Institutes Series, D. Reidel, Dordrecht, 1982, pp. 4396.CrossRefGoogle Scholar
[13]Davey, B. A. and Priestley, H. A., “Generalised piggyback dualities and applications to Ockham algebras”, Houston J. Math., (to appear).Google Scholar
[14]Davey, B. A. and Werner, H., “Dualities and equivalences for varieties of algebras”, in Contributions to Lattice Theory (Szeged 1980), Colloq. Math. Soc. János Bolyai 33, North-Holland, Amsterdam-New York, 1983, pp. 101275.Google Scholar
[15]Fowler, P. R., De Morgan Algebras, (ph.D. Thesis, Flinders University, Australia, 1980.)Google Scholar
[16]Goldberg, M. S., Distributive p-algebras and Ockham Algebras: a Topological Approach, (ph.D. Thesis, La Trobe University, Australia, 1979).Google Scholar
[17]Goldberg, M. S., “Distributive Ockham algebras: free algebras and injectivity”, Bull. Austral. Math. Soc. 24 (1981), 161203.CrossRefGoogle Scholar
[18]Grȁtzer, G., Lattice Theory: First Concepts and Distributive Lattices (Freeman, San Francisco, California, 1971).Google Scholar
[19]Hedrlín, Z. and Pultr, A., “Symmetric relations (undirected graphs) with given semigroup”, Monatsh. Math. 68 (1964), 421425.CrossRefGoogle Scholar
[20]Hedrlín, Z. and Pultr, A., “On full embeddings of categories of algebras”, Illinois J. Math. 10 (1966), 392406.CrossRefGoogle Scholar
[21]Kalman, J.A., “Lattices with involution”, Trans. Amer. Math. Soc. 87 (1958), 485491.CrossRefGoogle Scholar
[22]Koubek, V., “Infinite image homomorphism of distributive bounded lattoces”, lectures in Universal Algebra (Szeged 1983), Colloq. Math. Soc. Janos Bolyai 43 North Holland, Amsterdam – New York, (1985) 241281.Google Scholar
[23]Koubek, V. and Sichler, J., “Universal varieties of distributive double p-algebras”, Glasgow Math. J. 26 (1985), 121131.CrossRefGoogle Scholar
[24]Magill, K. D., “The semigroup of endomorphisms of a Boolean ring”, Semigroup Forum 4 (1972), 411416.Google Scholar
[25]Maxson, C. J., “On semigroups of Boolean ring endomorphisms”, Semigroup Forum 4 (1972), 7882).CrossRefGoogle Scholar
[26]Priestley, H. A., “Representation of distributive lattices by means of ordered Stone spaces”, Bull. London Math. Soc. 2 (1970), 186190.CrossRefGoogle Scholar
[27]Priestley, H. A., “Ordered topological spaces and the representation of distributive lattices”, Proc. London Math. Soc. (3) 24 (1972), 507530.CrossRefGoogle Scholar
[28]Priestley, H. A., “Ordered sets and duality for distributive lattices”, Ann. Discrete Math. 23 (1984), 3960.Google Scholar
[29]Pultr, A. and Trnková, V.Combinatorial, Algebraic and Topological Representations of Groups, Semigroups and Categories, (North-Holland, Amsterdam, 1980.)Google Scholar
[30]Schein, B. M., “Ordered sets, semilattices, distributive lattices Boolean algebras with homomorphic endomorphism semigroups”, Fund. Math. 68 (1970), 3150.CrossRefGoogle Scholar
[31]Urquhart, A., “Distributive lattices with a dual homomorphic operation”, Studia Logica 38 (1979), 201209.CrossRefGoogle Scholar