{"title":"实Weyl代数上的赋值和排序","authors":"Lara Vukšić","doi":"10.26493/1855-3974.2968.d23","DOIUrl":null,"url":null,"abstract":"The first Weyl algebra A1(k) over a field k is the k-algebra with two generators x, y subject to [y, x] = 1 and was first introduced during the development of quantum mechanics. In this article, we classify all valuations on the real Weyl algebra A1(R) whose residue field is R. We then use a noncommutative version of the Baer-Krull theorem from real algebraic geometry to classify all orderings on A1(R). As a byproduct of our studies, we settle two open problems in noncommutative valuation theory. First, we show that not all valuations on A1(R) with residue field R extend to a valuation on a larger ring R[y; δ], where R is the ring of Puiseux series, introduced by Marshall and Zhang in [12], with the same residue field, and characterize the valuations that do have such an extension. Second, we show that for valuations on noncommutative division rings, Kaplansky’s theorem that extensions by limits of pseudo-Cauchy sequences are immediate fails in general.","PeriodicalId":49239,"journal":{"name":"Ars Mathematica Contemporanea","volume":"15 1","pages":""},"PeriodicalIF":0.6000,"publicationDate":"2023-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Valuations and orderings on the real Weyl algebra\",\"authors\":\"Lara Vukšić\",\"doi\":\"10.26493/1855-3974.2968.d23\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The first Weyl algebra A1(k) over a field k is the k-algebra with two generators x, y subject to [y, x] = 1 and was first introduced during the development of quantum mechanics. In this article, we classify all valuations on the real Weyl algebra A1(R) whose residue field is R. We then use a noncommutative version of the Baer-Krull theorem from real algebraic geometry to classify all orderings on A1(R). As a byproduct of our studies, we settle two open problems in noncommutative valuation theory. First, we show that not all valuations on A1(R) with residue field R extend to a valuation on a larger ring R[y; δ], where R is the ring of Puiseux series, introduced by Marshall and Zhang in [12], with the same residue field, and characterize the valuations that do have such an extension. Second, we show that for valuations on noncommutative division rings, Kaplansky’s theorem that extensions by limits of pseudo-Cauchy sequences are immediate fails in general.\",\"PeriodicalId\":49239,\"journal\":{\"name\":\"Ars Mathematica Contemporanea\",\"volume\":\"15 1\",\"pages\":\"\"},\"PeriodicalIF\":0.6000,\"publicationDate\":\"2023-03-13\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Ars Mathematica Contemporanea\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.26493/1855-3974.2968.d23\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ars Mathematica Contemporanea","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.26493/1855-3974.2968.d23","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
The first Weyl algebra A1(k) over a field k is the k-algebra with two generators x, y subject to [y, x] = 1 and was first introduced during the development of quantum mechanics. In this article, we classify all valuations on the real Weyl algebra A1(R) whose residue field is R. We then use a noncommutative version of the Baer-Krull theorem from real algebraic geometry to classify all orderings on A1(R). As a byproduct of our studies, we settle two open problems in noncommutative valuation theory. First, we show that not all valuations on A1(R) with residue field R extend to a valuation on a larger ring R[y; δ], where R is the ring of Puiseux series, introduced by Marshall and Zhang in [12], with the same residue field, and characterize the valuations that do have such an extension. Second, we show that for valuations on noncommutative division rings, Kaplansky’s theorem that extensions by limits of pseudo-Cauchy sequences are immediate fails in general.
期刊介绍:
Ars mathematica contemporanea will publish high-quality articles in contemporary mathematics that arise from the discrete and concrete mathematics paradigm. It will favor themes that combine at least two different fields of mathematics. In particular, we welcome papers intersecting discrete mathematics with other branches of mathematics, such as algebra, geometry, topology, theoretical computer science, and combinatorics. The name of the journal was chosen carefully. Symmetry is certainly a theme that is quite welcome to the journal, as it is through symmetry that mathematics comes closest to art.