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Congruences on orthodox semigroups II

Published online by Cambridge University Press:  09 April 2009

John Meakin
Affiliation:
The University of Florida Gainesville, Florida and The University of NebraskaLincoln, Nebraska
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If ρ is a congruence on a regular semigroup S, then the kernel of ρ is defined to be the set of ρ-classes which contain idempotents of S. Preston [7] has proved that two congruences on a regular semigroup coincide if and only if they have the same kernel: this naturally poses the problem of characterizing the kernel of a congruence on a regular semigroup and reconstructing the congruence from its kernel. In some sense this problem has been resolved by the author in [5]. Using the well-known theorem of M. Teissier (see for example, A. H. Clifford and G. B. Preston [1], Vol. II, Theorem 10.6), it is possible to characterize the kernel of a congruence on a regular semigroup S as a set A = {Ai: iI} of subsets of S which satisfy the Teissier-Vagner-Preston conditions:

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1972

References

[1]Clifford, A. H. and Preston, G. B., The algebraic theory of semigroups (Math. Surveys, number 7, Amer. Math. Soc., Vol. I, 1961, Vol. II, 1967).Google Scholar
[2]Hall, T. E., ‘On regular semigroups whose idempotents from a subsemigroup’, Bull. Austral. Math. Soc. 1 (1969), 195208.CrossRefGoogle Scholar
[3]Lallement, G., ‘Demi-groupes réguliers. Annali di Mat. pura et applicata 77 (1967), 47130.Google Scholar
[4]Meakin, J. C., ‘Congruences on orthodox semigroups’, J. Austral. Math. Soc. 12 (1971), 323341.CrossRefGoogle Scholar
[5]Meakin, J. C., ‘Congruences on regular semigroups’, Semigroup Forum, Vol. 1, No. 3, 1970, 232235.CrossRefGoogle Scholar
[6]Munn, W. D., ‘Brandt congruences on inverse semigroups’. Proc. London Math. Soc. 14 (1964), 154164.Google Scholar
[7]Preston, G. B., ‘Inverse semigroups’, J. London Math. Soc. 29 (1954), 396403.CrossRefGoogle Scholar
[8]Reilly, N. R. and Scheiblich, H. E., ‘Congruences on regular semigroups’, Pacific J. Math. 23 (1967), 349360.Google Scholar