{ "id": "2001.06134", "version": "v1", "published": "2020-01-17T01:49:37.000Z", "updated": "2020-01-17T01:49:37.000Z", "title": "Varieties of Regular Pseudocomplemented de Morgan Algebras", "authors": [ "M. E. Adams", "H. P. Sankappanavar", "JĂșlia Vaz de Carvalho" ], "comment": "29 pages; 2 figures", "doi": "10.1007/s11083-019-09518-y", "categories": [ "math.LO" ], "abstract": "In this paper, we investigate the varieties $\\mathbf M_n$ and $\\mathbf K_n$ of regular pseudocomplemented de Morgan and Kleene algebras of range $n$, respectively. Priestley duality as it applies to pseudocomplemented de Morgan algebras is used. We characterise the dual spaces of the simple (equivalently, subdirectly irreducible) algebras in $\\mathbf M_n$ and explicitly describe the dual spaces of the simple algebras in $\\mathbf M_1$ and $\\mathbf K_1$. We show that the variety $\\mathbf M_1$ is locally finite, but this property does not extend to $\\mathbf M_n$ or even $\\mathbf K_n$ for $n \\geq 2$. We also show that the lattice of subvarieties of $\\mathbf K_1$ is an $\\omega + 1$ chain and the cardinality of the lattice of subvarieties of either $\\mathbf K_2$ or $\\mathbf M_1$ is $2^{\\omega}$. A description of the lattice of subvarieties of $\\mathbf M_1$ is given.", "revisions": [ { "version": "v1", "updated": "2020-01-17T01:49:37.000Z" } ], "analyses": { "subjects": [ "06D30", "06D15", "03G25", "08B15", "06D50", "03G10" ], "keywords": [ "morgan algebras", "dual spaces", "subvarieties", "simple algebras", "priestley duality" ], "tags": [ "journal article" ], "publication": { "publisher": "Springer" }, "note": { "typesetting": "TeX", "pages": 29, "language": "en", "license": "arXiv", "status": "editable" } } }