{"id":1065,"date":"2022-02-25T19:30:03","date_gmt":"2022-02-25T18:30:03","guid":{"rendered":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/?page_id=1065"},"modified":"2023-12-12T13:00:49","modified_gmt":"2023-12-12T12:00:49","slug":"courses-2022","status":"publish","type":"page","link":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/courses\/courses-2022\/","title":{"rendered":"Courses 2022"},"content":{"rendered":"<p>Dal 28 novembre 2022 al 02 dicembre 2022 la Dott.ssa Laura Cossu, University of Graz, terra&#8217; un corso di dottorato su: <span dir=\"ltr\" role=\"presentation\">Factorizations in monoids and rings<\/span><\/p>\n<p><span dir=\"ltr\" role=\"presentation\"><br \/>\nMany problems in algebra involve the decomposition of certain elements of a ring (or more generally<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">of a monoid) into a product of certain other elements (hereinafter generically referred to as building<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">blocks) that are in some sense minimal. The classical theory of factorization investigates factorizations<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">in which the building blocks are atoms, i.e., non-unit elements of a monoid that are not products of<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">two non-units. For example, it is well known that every non-zero non-unit of a Dedekind domain (more<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">generally, of a Noetherian domain) can be written as a finite product of atoms and that in general<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">such decompositions are not unique. On the other hand, examples of factorizations that lie beyond the<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">scope of the classical theory include additive decompositions into multiplicative units in rings; cyclic<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">decompositions of permutations in the symmetric group of degree n; idempotent factorizations of the<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">\u201csingular elements\u201d of a monoid; and so on.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">After an introductory overview of the history and main results in the classical framework, in this<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">course, we combine the language of monoids and preorders (partial orders that are not necessarily an-<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">tisymmetric) to make first steps towards the construction of a \u201cunified theory of factorization\u201d.<\/span> <span dir=\"ltr\" role=\"presentation\">In<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">particular, we prove an abstract existence theorem that recover, among others, a classical theorem of<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">Cohn on atomic factorizations in cancellative monoids, a classical result by Anderson and Valdes-Leon<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">on \u201cirreducible factorizations\u201d in commutative monoids, but also a theorem by Erdos on idempotent fac-<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">torizations of square singular matrices over fields. We also introduce a notion of \u201cminimal factorization\u201d,<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">suitable for the new abstract setting, and we qualify and quantify the related non-uniqueness properties<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">in specific cases but also in some generality. Examples will help to motivate and illustrate the theory.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">Prerequisites:<\/span> <span dir=\"ltr\" role=\"presentation\">Standard knowledge of (basic) algebraic structures and (binary) relations.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">Duration of the course:<\/span> <span dir=\"ltr\" role=\"presentation\">10 hours.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">Exam:<\/span> <span dir=\"ltr\" role=\"presentation\">Written. Writing of a short essay.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">References<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">[1] L. Cossu and S. Tringali,<\/span> <span dir=\"ltr\" role=\"presentation\">Abstract Factorization Theorems with Applications to Idempotent Factor-<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">izations<\/span><span dir=\"ltr\" role=\"presentation\">, e-print (Aug. 2021),<\/span> <span dir=\"ltr\" role=\"presentation\">arXiv:2108.12379<\/span><span dir=\"ltr\" role=\"presentation\">.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">[2] L. Cossu and S. Tringali,<\/span> <span dir=\"ltr\" role=\"presentation\">Factorization under Local Finiteness Conditions<\/span><span dir=\"ltr\">, e-print (Aug. 2022),<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">arXiv:2208.05869<\/span><span dir=\"ltr\" role=\"presentation\">.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">[3] A. Geroldinger and F. Halter-Koch,<\/span> <span dir=\"ltr\" role=\"presentation\">Non-Unique Factorizations. Algebraic, Combinatorial and An-<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">alytic Theory<\/span><span dir=\"ltr\" role=\"presentation\">, Pure Appl. Math.<\/span> <span dir=\"ltr\" role=\"presentation\">278<\/span><span dir=\"ltr\" role=\"presentation\">, Chapman &amp; Hall\/CRC, Boca Raton (FL), 2006.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">[4] S. Tringali,<\/span> <span dir=\"ltr\" role=\"presentation\">An Abstract Factorization Theorem and Some Applications<\/span><span dir=\"ltr\" role=\"presentation\">, J. Algebra 602 (2022), 352\u2013<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">380.<\/span><br role=\"presentation\" \/><span dir=\"ltr\" role=\"presentation\">1<\/span><\/p>\n<p>Il calendario delle lezioni \u00e8 il seguente: Luned\u00ec 28 novembre dalle 16:00 alle 18:00 Aula B Marted\u00ec 29 novembre dalle 16:00 alle 18:00 Aula A Mercoled\u00ec 30 novembre dalle 16:00 alle 18:00 Aula A Gioved\u00ec 1 dicembre dalle 16:00 alle 18:00 Aula A Venerd\u00ec 2 dicembre dalle 16:00 alle 18:00 Aula A<\/p>\n<p>&nbsp;<\/p>\n<hr \/>\n<p>Dal 20 al 30 giugno i Visiting Professors M. Lucia e P. Sicbaldi terranno\u00a0un\u00a0corso intitolato\u00a0&#8220;Geometric\u00a0Analysis&#8221;\u00a0per\u00a0un\u00a0totale\u00a0di 20 ore di lezione (dieci ciascuno). Le informazioni si trovano al link: <a href=\"https:\/\/www.unica.it\/unica\/page\/it\/antonio_greco_avs_geometric_analysis\" target=\"_blank\" rel=\"noopener noreferrer\">https:\/\/www.unica.it\/unica\/page\/it\/antonio_greco_avs_geometric_analysis<\/a><\/p>\n<hr \/>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Dal 28 novembre 2022 al 02 dicembre 2022 la Dott.ssa Laura Cossu, University of Graz, terra&#8217; un corso di dottorato su: Factorizations in monoids and rings Many problems in algebra involve the decomposition of certain elements of a ring (or more generallyof a monoid) into a product of certain other elements (hereinafter generically referred to as buildingblocks) that are in some sense minimal. The classical theory of factorization investigates factorizationsin which the building blocks are atoms, i.e., non-unit elements of a monoid that are not products oftwo non-units. For example, it is well known that every non-zero non-unit of a <a href='https:\/\/dottorati.unica.it\/matematicaeinformatica\/courses\/courses-2022\/' class='excerpt-more'>[&#8230;]<\/a><\/p>\n","protected":false},"author":3006,"featured_media":0,"parent":161,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1065","page","type-page","status-publish","hentry","post-seq-1","post-parity-odd","meta-position-corners","fix"],"_links":{"self":[{"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/pages\/1065","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/users\/3006"}],"replies":[{"embeddable":true,"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/comments?post=1065"}],"version-history":[{"count":13,"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/pages\/1065\/revisions"}],"predecessor-version":[{"id":1273,"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/pages\/1065\/revisions\/1273"}],"up":[{"embeddable":true,"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/pages\/161"}],"wp:attachment":[{"href":"https:\/\/dottorati.unica.it\/matematicaeinformatica\/wp-json\/wp\/v2\/media?parent=1065"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}