{"id":349,"date":"2021-05-02T00:01:08","date_gmt":"2021-05-02T00:01:08","guid":{"rendered":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/?page_id=349"},"modified":"2022-07-04T11:05:05","modified_gmt":"2022-07-04T11:05:05","slug":"matlis-semi-regularity-and-semi-coherence-in-trivial-ring-extensions-a-survey","status":"publish","type":"page","link":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/matlis-semi-regularity-and-semi-coherence-in-trivial-ring-extensions-a-survey\/","title":{"rendered":"Matlis\u2019 semi-regularity and semi-coherence in trivial ring extensions: a survey"},"content":{"rendered":"\n<div style=\"height:11px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div style=\"height:63px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\"><\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:25%\">\n<figure class=\"wp-block-image size-full is-resized is-style-default\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-content\/uploads\/2022\/03\/logovf-4.png\" alt=\"\" class=\"wp-image-752\" width=\"150\" height=\"200\"\/><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:70%\">\n<p style=\"font-size:21px\"><strong>Moroccan Journal of Algebra and Geometry with Applications<\/strong><\/p>\n\n\n\n<p><a href=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/vol-1-no-1\" data-type=\"URL\" data-id=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/vol-1-no-1\">Latest articles<\/a><\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div style=\"height:100px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:1200px\"><\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\"><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:100%\">\n<p class=\"has-text-align-center has-text-color has-huge-font-size\" style=\"color:#060182\"><strong><em>Matlis\u2019 semi-regularity and semi-coherence in trivial ring <br>extensions: a survey<\/em><\/strong><\/p>\n<\/div>\n<\/div>\n\n\n\n<p class=\"has-text-align-center\" style=\"font-size:18.5px\"><strong>Salah-Eddine Kabbaj&nbsp;<\/strong><i class=\"fas fa-envelope\"><\/i><br> Department of Mathematics, KFUPM, Dhahran 31261, Saudi Arabia<\/p>\n\n\n\n<div style=\"height:35px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-text-align-center has-text-color\" style=\"color:#232222;font-size:16px\"><span style=\"color:#626161\" class=\"color\">Pages 1-17 |  Received 09 April 2021,  Accepted 29 May 2021, Published 01 June 2022  <\/span><\/p>\n\n\n\n<div style=\"height:31px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:25%\"><\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:250%\">\n<div style=\"height:51px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"has-large-font-size\"><strong><span style=\"color:#060182\" class=\"color\">Abstract<\/span><\/strong><\/p>\n\n\n\n<p class=\"has-small-font-size\">In 1985, Matlis defined a ring R to be semi-coherent if Hom<sub>R<\/sub>(M, N) is a submodule of a flat R-module for any injective R-modules M and N. Then, inspired by this definition and von Neumann regularity, he defined a ring to be semi-regular if any module can be embedded in a flat module. He then established a connection of this notion with coherence by proving that semi-regularity is a local property in the class of coherent rings. This survey paper tracks three recent works which investigate these notions in trivial ring extensions (also called Nagata idealizations) and contribute to the study of homological aspects of these constructions. Section 2 deals with the transfer of semi-regularity along with related concepts, such ascoherence, in trivial ring extensions issued from integral domains.  All along the section, the new results are put in use to enrich the literature with new families of examples subject to semi-regularity. Section 3 features the transfer of semi-regularity and semi-coherence in trivial ring extensions issued from rings (with zero-divisors). The new results are used to enrich the literature with new examples of semi-regularor semi-coherent rings which arise as trivial ring extensions, and hence validate some questions left openin the literature. Section 4 proves an extension of Zaks\u2019 conjecture on integral domains with semi-regular proper homomorphic images (with respect to finitely generated ideals) to arbitrary rings (i.e., possibly withzero-divisors). The main result extends and recovers two classical results, due to Levy (1966) and Matlis (1985), on Noetherian rings and Pr\u00fcfer domains, respectively. It also proves a global version of a result of Couchot (2003) on chained (valuation) rings. As an application, new examples of rings with semi-regular proper homomorphic images are constructed through transfer results on trivial ring extensions.   <\/p>\n\n\n\n<p class=\"has-small-font-size\"><span style=\"color:#060182\" class=\"color\"><strong>Keywords<\/strong>:<\/span>&nbsp; Semi-regular ring, IF-ring, coherent ring, arithmetical ring, chained ring, quasi-Frobenius ring, von Neumann regular ring, self fp-injective ring, Pr\u00fcfer domain, Dedekind domain, trivial ring extension, Nagata idealization.                   <\/p>\n\n\n\n<p class=\"has-small-font-size\"><span style=\"color:#060182\" class=\"color\"><strong>MSC numbers<\/strong>:<\/span> Primary 13C10, 13C11, 13E05, 13F05, 13H10; Secondary 16A30, 16A50, 16A52.<\/p>\n\n\n\n<p class=\"has-small-font-size\"><strong>Downloads:<\/strong> <a href=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-content\/uploads\/2022\/07\/0101MJAGA01_17.pdf\" data-type=\"URL\" data-id=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-content\/uploads\/2022\/07\/0101MJAGA01_17.pdf\">Full-text PDF<\/a>                                <\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:25%\"><\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:25%\"><\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:800px\"><a href=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-content\/uploads\/2022\/07\/0101MJAGA01_17.pdf\" class=\"pdfemb-viewer\" style=\"width:700px;height:950px;\" data-width=\"700\" data-height=\"950\" data-toolbar=\"bottom\" data-toolbar-fixed=\"off\">0101MJAGA01_17<\/a>\n<p class=\"wp-block-pdfemb-pdf-embedder-viewer\"><\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:25%\"><\/div>\n<\/div>\n\n\n\n<div style=\"height:96px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div class=\"wp-block-buttons is-content-justification-right is-layout-flex wp-container-core-buttons-is-layout-765c4724 wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button is-style-outline is-style-outline--1\"><a class=\"wp-block-button__link\" style=\"border-radius:100px\">Previous article <\/a><\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div class=\"wp-block-buttons is-content-justification-center is-layout-flex wp-container-core-buttons-is-layout-16018d1d wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button is-style-outline is-style-outline--2\"><a class=\"wp-block-button__link\" href=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/vol-1-no-1\" style=\"border-radius:100px\"><strong>View<\/strong>&nbsp;issue table of contents<\/a><\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div class=\"wp-block-buttons is-content-justification-left is-layout-flex wp-container-core-buttons-is-layout-fdcfc74e wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button is-style-outline is-style-outline--3\"><a class=\"wp-block-button__link\" href=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/on-constructing-angles-with-prescribed-vertex-and-measure-in-the-upper-half-plane-modelof-hyperbolic-geometry\/\" style=\"border-radius:100px\"><strong>Next<\/strong>&nbsp;article<\/a><\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Moroccan Journal of Algebra and Geometry with Applications Latest articles Matlis\u2019 semi-regularity and semi-coherence in trivial ring extensions: a survey Salah-Eddine Kabbaj&nbsp; Department of Mathematics, KFUPM, Dhahran 31261, Saudi Arabia Pages 1-17 | Received 09 April 2021, Accepted 29 May 2021, Published 01 June 2022 Abstract In 1985, Matlis defined a ring R to be <a class=\"read-more-link\" href=\"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/matlis-semi-regularity-and-semi-coherence-in-trivial-ring-extensions-a-survey\/\">Read More<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"template-page-builder.php","meta":{"footnotes":""},"class_list":["post-349","page","type-page","status-publish","hentry","entry"],"_links":{"self":[{"href":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-json\/wp\/v2\/pages\/349","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-json\/wp\/v2\/comments?post=349"}],"version-history":[{"count":140,"href":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-json\/wp\/v2\/pages\/349\/revisions"}],"predecessor-version":[{"id":1112,"href":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-json\/wp\/v2\/pages\/349\/revisions\/1112"}],"wp:attachment":[{"href":"https:\/\/ced.fst-usmba.ac.ma\/p\/mjaga\/wp-json\/wp\/v2\/media?parent=349"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}