arXiv subjects
Publications and source records attributed to Dietmar Schweigert.
We invent the notion of a {\it dimension of a variety} $V$ as the cardinality of all its proper {\it derived} subvarieties (of the same type). The dimensions of varieties of lattices, varieties of regular bands and other general algebraic structures are determined.
We invent the notion of a derived and fluid variety. Fluid variety has no proper derived variety as its subvariety. We examine some properties of fluid and derived varieties. Examples of such varieties of bands are presented.
We show that the algebra $\mathbf{R} = \bigl(R; \wedge, \veebar, 0, \bar{f}_i(x) (i \in I)\bigr)$ is central polynomially complete and finite.
In the paper we consider the notion of hyper-quasi-identities and hyperquasivarieties as a generalization of the concept of quasi-identity and quasivariety invented by A. I. Mal'cev.