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Free products of hopfian lattices

Published online by Cambridge University Press:  09 April 2009

G. Grätzer
Affiliation:
Department of Mathematics, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
J. Sichler
Affiliation:
Department of Mathematics, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
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In this paper we are going to prove the following results:

Theorem 1. There exist two bounded hopfian lattices such that their {0,1}- free product is not hopfian.

Theorem 2. There exist two hopfian lattices such that their free product is not hopfian.

In Theorem 2 free product (coproduct, sum) has its usual meaning (see, for instance, [4]); in Theorem 1 we use the usual definition but all lattices are assumed to be bounded (that is, having a least element 0 and largest element 1) and all homomorphisms are assumed to be {0, l}-homomorphisms (that is, homomorphisms preserving 0 and 1).

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1974

References

[1]Chen, C. C. and Grätzer, G., ‘On the construction of complemented lattices’, J. Algebra 11 (1969), 5663.CrossRefGoogle Scholar
[2]Dey, I. M. S. and Neumann, Hanna, ‘The Hopf property of free products’, Math. Z. 117 (1970), 325339.CrossRefGoogle Scholar
[3]Evans, T., ‘Finitely presented loops, lattices, etc. are hopfian’, J. London. Math. Soc. 44 (1969), 551552.CrossRefGoogle Scholar
[4]Grätzer, G., Lattice Theory: First Concepts and Distributive Lattices (W. H. Freeman and Co., San Francisco, 1971).Google Scholar
[5]Grätzer, G., ‘A reduced free product of lattices’, Fund. Math. 73 (1971), 2127.CrossRefGoogle Scholar
[6]Grätzer, G., Lakser, H. and Platt, C. R., ‘Free products of lattices’, Fund Math. 69 (1970), 233240.CrossRefGoogle Scholar
[7]Grätzer, G. and Sichler, J., ‘On the endomprophism semigroup (and category) of bounded lattices’, Pacific J. Math. 35 (1970), 639647.CrossRefGoogle Scholar
[8]Hedrlin, Z. and Sichler, J., ‘Any boundable binding category contains a proper class of mutually disjoint copies of itself’, Algebra Universalis 1 (1971), 97103.CrossRefGoogle Scholar
[9]Hell, P., ‘Full embeddings into some categories of graphs’, Algebra Universalis 2 (1972), 125137.CrossRefGoogle Scholar
[10]Jónsson, B., ‘Sublattices of a free lattice’, Canad. J. Math. 13 (1961), 256264.CrossRefGoogle Scholar
[11] Lakser, H., ‘Simple sublattices of free products of lattices’, manuscript.Google Scholar
[12]Sichler, J., ‘Nonconstant endomorphisms of lattices’, Proc. Amer. Math. Soc. 34 (1972), 6770.CrossRefGoogle Scholar
[13] Sichler, J., ‘An example of a pair of hopfian groups whose free product is not hopfian’, manuscript.Google Scholar
[14]Whitman, P. M., ‘Free lattices I and II’, Ann. Math. 42 (1941), 325330; 43 (1942), 104–115.CrossRefGoogle Scholar