Skip to main content
Log in

Special elements of the lattice of monoid varieties

  • Published:
Algebra universalis Aims and scope Submit manuscript

Abstract

We completely classify all neutral and costandard elements in the lattice \(\mathbb {MON}\) of all monoid varieties. Further, we prove that an arbitrary upper-modular element of \(\mathbb {MON}\) except the variety of all monoids is either a completely regular or a commutative variety. Finally, we verify that all commutative varieties of monoids are codistributive elements of \(\mathbb {MON}\). Thus, the problems of describing codistributive or upper-modular elements of \(\mathbb {MON}\) are completely reduced to the completely regular case.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Burris, S., Nelson, E.: Embedding the dual of \(\Pi _\infty \) in the lattice of equational classes of semigroups. Algebra Universalis 1, 248–254 (1971)

    Article  MathSciNet  MATH  Google Scholar 

  2. Burris, S., Nelson, E.: Embedding the dual of \(\Pi _m\) in the lattice of equational classes of commutative semigroups. Proc. Am. Math. Soc. 3, 37–39 (1971)

    Google Scholar 

  3. Grätzer, G.: Lattice Theory: Foundation. Birkhäuser, Springer Basel AG, Basel (2011)

    Book  MATH  Google Scholar 

  4. Gusev, S.V.: On the lattice of overcommutative varieties of monoids. Izv. VUZ Matem (5), 28–32 (2018) (Russian; Engl. translation is available at https://arxiv.org/abs/1702.08749)

  5. Gusev, S.V., Vernikov, B.M: Chain varieties of monoids. Dissertationes Math. (in press). https://arxiv.org/abs/1707.05530

  6. Head, T.J.: The varieties of commutative monoids. Nieuw Arch. Wiskd. III Ser. 1(6), 203–206 (1968)

    MathSciNet  MATH  Google Scholar 

  7. Jackson, M.: Finiteness properties of varieties and the restriction to finite algebras. Semigroup Forum 7, 154–187 (2005)

    MathSciNet  MATH  Google Scholar 

  8. Jackson, M., Lee, E.W.H.: Monoid varieties with extreme properties. Trans. Am. Math. Soc. https://doi.org/10.1090/tran/7091 (in press)

  9. Ježek, J.: The lattice of equational theories. Part I: modular elements. Czechoslov. Math. J. 31, 127–152 (1981)

    MATH  Google Scholar 

  10. Lee, E.W.H.: Varieties generated by \(2\)-testable monoids. Stud. Sci. Math. Hung. 4(9), 366–389 (2012)

    MathSciNet  MATH  Google Scholar 

  11. Lee, E.W.H.: Inherently non-finitely generated varieties of aperiodic monoids with central idempotents. Zapiski Nauchnykh Seminarov POMI (Notes of Scientific Seminars of the St. Petersburg Branch of the Math. Institute of the Russ. Acad. of Sci.) 423, 166–182 (2014)

  12. Pollák, Gy: Some lattices of varieties containing elements without cover. Quad. Ric. Sci. 109, 91–96 (1981)

    MathSciNet  MATH  Google Scholar 

  13. Šešelja, B., Tepavčević, A.: Weak Congruences in Universal Algebra. Institute of Mathematics, Symbol, Novi Sad (2001)

    MATH  Google Scholar 

  14. Shevrin, L.N., Vernikov, B.M., Volkov, M.V.: Lattices of semigroup varieties. Izv. VUZ Matem. 3, 3–36 (2009) (Russian; Engl. translation: Russian Math. (Iz. VUZ) 53, No. 3, 1–28 (2009))

  15. Vernikov, B.M.: Upper-modular elements of the lattice of semigroup varieties. Algebra Universalis 5(9), 405–428 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  16. Vernikov, B.M.: Upper-modular elements of the lattice of semigroup varieties. II. Fundam. Appl. Math. 14(7), 43–51 (2008) (Russian; Engl. translation: J. Math. Sci. 164, 182–187 (2010))

  17. Vernikov, B.M.: Codistributive elements of the lattice of semigroup varieties. Izv. VUZ Mat. No. 7, 13–21 (2011) (Russian; Engl. translation: Russian Math. (Iz. VUZ) 55, No. 7, 9–16 (2011))

  18. Vernikov, B.M.: Special elements in lattices of semigroup varieties. Acta Sci. Math. (Szeged) 8(1), 79–109 (2015)

    Article  MathSciNet  MATH  Google Scholar 

  19. Vernikov, B.M.: Upper-modular and related elements of the lattice of commutative semigroup varieties. Semigroup Forum 9(4), 696–711 (2017)

    Article  MathSciNet  MATH  Google Scholar 

  20. Volkov, M.V.: Modular elements of the lattice of semigroup varieties. Contrib. Gen. Algebra 1(6), 275–288 (2005)

    MathSciNet  MATH  Google Scholar 

  21. Wismath, S.L.: The lattice of varieties and pseudovarieties of band monoids. Semigroup Forum 3(3), 187–198 (1986)

    Article  MathSciNet  MATH  Google Scholar 

Download references

Acknowledgements

The author is sincerely grateful to Professor B.M. Vernikov for his great assistance in the improvement of the initial version of the manuscript and to Professor M.V. Volkov for helpful discussions.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Sergey V. Gusev.

Additional information

Presented by M. Jackson.

The work is supported by the Russian Foundation for Basic Research (Grant 17-01-00551) and by the Ministry of Education and Science of the Russian Federation (project 1.6018.2017/8.9).

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Gusev, S.V. Special elements of the lattice of monoid varieties. Algebra Univers. 79, 29 (2018). https://doi.org/10.1007/s00012-018-0513-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s00012-018-0513-0

Mathematics Subject Classification

Keywords

Navigation