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Keywords:
mode; differential groupoid; lattice of subquasivarieties; $\Cal Q$-universal quasivariety
Summary:
The main result of Romanowska A., Roszkowska B., {\it On some groupoid modes\/}, Demonstratio Math. {\bf 20} (1987), no. 1--2, 277--290, provides us with an explicit description of the lattice of varieties of differential groupoids. In the present article, we show that this variety is $\Cal Q$-universal, which means that there is no convenient explicit description for the lattice of quasivarieties of differential groupoids. We also find an example of a subvariety of differential groupoids with a finite number of subquasivarieties.
References:
[1] Adams M.E., Adaricheva K.V., Dziobiak W., Kravchenko A.V.: Open problems related to the problem of Birkhoff and Maltsev. Studia Logica 78 (2004), 357-378. MR 2108035
[2] Gorbunov V.A.: Algebraic Theory of Quasivarieties. Plenum New York-London-Moscow (1998). MR 1654844 | Zbl 0986.08001
[3] Ježek J., Kepka T.: Medial groupoids. Rozpravy Československé Akad. Věd, Řada Mat. Přírod. Věd 93 (1983), 2. MR 0734873
[4] Płonka J.: On $k$-cyclic groupoids. Math. Japon. 30 (1985), 3 371-382. MR 0803288
[5] Romanowska A.: On some representations of groupoid modes satisfying the reduction law. Demonstratio Math. 21 (1988), 4 943-960. MR 0993839 | Zbl 0677.20057
[6] Romanowska A., Roszkowska B.: On some groupoid modes. Demonstratio Math. 20 (1987), 1-2 277-290. MR 0941422 | Zbl 0669.08005
[7] Romanowska A., Roszkowska B.: Representation of $n$-cyclic groupoids. Algebra Universalis 26 (1989), 1 7-15. DOI 10.1007/BF01243869 | MR 0981422
[8] Romanowska A.B., Smith J.D.H.: Differential groupoids. Contributions to General Algebra 7 Proc. Vienna Conf. (Vienna, 1990) 283-290 Teubner Stuttgart (1991). MR 1143092 | Zbl 0744.20055
[9] Romanowska A.B., Smith J.D.H.: Modes. World Scientific Singapore (2002). MR 1932199 | Zbl 1012.08001
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