{"title":"Highest Weight Modules for Affine and Loop Superalgebras of (mathfrak {osp}_{1|2}(mathbb C))","authors":"Fulin Chen, Xin Huang, Shaobin Tan","doi":"10.1007/s10468-024-10292-8","DOIUrl":"10.1007/s10468-024-10292-8","url":null,"abstract":"<div><p>This paper is about the highest weight module theory for affine superalgebra <span>(widetilde{mathfrak g})</span> of <span>({mathfrak g}={mathfrak {osp}_{1|2}(mathbb C)})</span> and loop superalgebra <span>({mathfrak g}{otimes }{mathbb {C}}[t,t^{-1}])</span>. Among the main results, we obtain (i) a necessary and sufficient condition for Verma type <span>(ell )</span>-highest weight <span>(widetilde{mathfrak g})</span>-modules to be irreducible; (ii) a free field(-like) realization of all irreducible <span>(ell )</span>-highest weight <span>(widetilde{mathfrak g})</span>-modules; (iii) a character formula for all irreducible <span>(ell )</span>-highest weight <span>(widetilde{mathfrak g})</span>-modules with finite dimensional weight spaces. We also obtain three similar results for highest weight <span>({mathfrak g}{otimes }{mathbb {C}}[t,t^{-1}])</span>-modules.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 6","pages":"2099 - 2130"},"PeriodicalIF":0.5,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Automorphisms of Quantum Toroidal Algebras from an Action of the Extended Double Affine Braid Group","authors":"Duncan Laurie","doi":"10.1007/s10468-024-10291-9","DOIUrl":"10.1007/s10468-024-10291-9","url":null,"abstract":"<div><p>We first construct an action of the extended double affine braid group <span>(mathcal {ddot{B}})</span> on the quantum toroidal algebra <span>(U_{q}(mathfrak {g}_{textrm{tor}}))</span> in untwisted and twisted types. As a crucial step in the proof, we obtain a finite Drinfeld new style presentation for a broad class of quantum affinizations. In the simply laced cases, using our action and certain involutions of <span>(mathcal {ddot{B}})</span> we produce automorphisms and anti-involutions of <span>(U_{q}(mathfrak {g}_{textrm{tor}}))</span> which exchange the horizontal and vertical subalgebras. Moreover, they switch the central elements <i>C</i> and <span>(k_{0}^{a_{0}}dots k_{n}^{a_{n}})</span> up to inverse. This can be viewed as the analogue, for these quantum toroidal algebras, of the duality for double affine braid groups used by Cherednik to realise the difference Fourier transform in his celebrated proof of the Macdonald evaluation conjectures. Our work generalises existing results in type <i>A</i> due to Miki which have been instrumental in the study of the structure and representation theory of <span>(U_{q}(mathfrak {sl}_{n+1,textrm{tor}}))</span>.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 6","pages":"2067 - 2097"},"PeriodicalIF":0.5,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10468-024-10291-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142995845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Deformed Tanisaki-Garsia-Procesi Modules","authors":"Maico Freitas, Evgeny Mukhin","doi":"10.1007/s10468-024-10288-4","DOIUrl":"10.1007/s10468-024-10288-4","url":null,"abstract":"<div><p>The polynomial ideals studied by A. Garsia and C. Procesi play an important role in the theory of Kostka polynomials. We give multiparameter flat deformations of these ideals and define an action of the extended affine symmetric group on the corresponding quotient algebras multiplied by the sign representation. We show that the images of these modules under the affine Schur-Weyl duality are dual to the local Weyl modules for the loop algebra <span>(mathfrak {sl}_{n+1}[t^{pm 1}])</span>.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 6","pages":"2019 - 2044"},"PeriodicalIF":0.5,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142994937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Note on Schur-Weyl Dualities for GL(m) and GL(m|n)","authors":"František Marko","doi":"10.1007/s10468-024-10290-w","DOIUrl":"10.1007/s10468-024-10290-w","url":null,"abstract":"<div><p>We use a unified elementary approach to prove the second part of classical, mixed, super, and mixed super Schur-Weyl dualities for general linear groups and supergroups over an infinite ground field of arbitrary characteristic. These dualities describe the endomorphism algebras of the tensor space and mixed tensor space, respectively, over the group algebra of the symmetric group and the Brauer wall algebra, respectively. Our main new results are the second part of the mixed Schur-Weyl dualities and mixed super Schur-Weyl dualities over an infinite ground field of positive characteristic.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 5","pages":"1957 - 1979"},"PeriodicalIF":0.5,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142264524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Homologically Smooth Connected Cochain DGAs","authors":"X.-F. Mao","doi":"10.1007/s10468-024-10287-5","DOIUrl":"10.1007/s10468-024-10287-5","url":null,"abstract":"<div><p>Let <span>(mathscr {A})</span> be a connected cochain DG algebra such that <span>(H(mathscr {A}))</span> is a Noetherian graded algebra. We give some criteria for <span>(mathscr {A})</span> to be homologically smooth in terms of the singularity category, the cone length of the canonical module <i>k</i> and the global dimension of <span>(mathscr {A})</span>. For any cohomologically finite DG <span>(mathscr {A})</span>-module <i>M</i>, we show that it is compact when <span>(mathscr {A})</span> is homologically smooth. If <span>(mathscr {A})</span> is in addition Gorenstein, we get </p><div><div><span>$$begin{aligned} textrm{CMreg}M = textrm{depth}_{mathscr {A}}mathscr {A} + mathrm {Ext.reg}, M<infty , end{aligned}$$</span></div></div><p>where <span>(textrm{CMreg}M)</span> is the Castelnuovo-Mumford regularity of <i>M</i>, <span>(textrm{depth}_{mathscr {A}}mathscr {A})</span> is the depth of <span>(mathscr {A})</span> and <span>( mathrm {Ext.reg}, M)</span> is the Ext-regularity of <i>M</i>.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 5","pages":"1931 - 1955"},"PeriodicalIF":0.5,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Modified Ariki-Koike Algebra and Yokonuma-Hecke like Relations","authors":"Myungho Kim, Sungsoon Kim","doi":"10.1007/s10468-024-10286-6","DOIUrl":"10.1007/s10468-024-10286-6","url":null,"abstract":"<div><p>We find new presentations of the modified Ariki-Koike algebra (known also as Shoji’s algebra) <span>(mathcal {H}_{n,r})</span> over an integral domain <i>R</i> associated with a set of parameters <span>(q,u_1,ldots ,u_r)</span> in <i>R</i>. It turns out that the algebra <span>(mathcal {H}_{n,r})</span> has a set of generators <span>(t_1,ldots ,t_n)</span> and <span>(g_1,ldots g_{n-1})</span> subject to some defining relations similar to the relations of Yokonuma-Hecke algebra. We also obtain a presentation of <span>(mathcal {H}_{n,r})</span> which is independent of the choice of <span>(u_1,ldots u_r)</span>. As applications of the presentations, we find an explicit and direct isomorphism between the modified Ariki-Koike algebras with different choices of parameters <span>((u_1,ldots ,u_r))</span>. We also find an explicit trace form on the algebra <span>(mathcal {H}_{n,r})</span> which is symmetrizing provided the parameters <span>(u_1,ldots , u_r)</span> are invertible in <i>R</i>. We show that the symmetric group <span>(mathfrak {S}(r))</span> acts on the algebra <span>(mathcal H_{n,r})</span>, and find a basis and a set of generators of the fixed subalgebra <span>(mathcal H_{n,r}^{mathfrak {S}(r)})</span>.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 5","pages":"1909 - 1930"},"PeriodicalIF":0.5,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vinit Sinha, Amit Kuber, Annoy Sengupta, Bhargav Kale
{"title":"Hammocks for Non-Domestic String Algebras","authors":"Vinit Sinha, Amit Kuber, Annoy Sengupta, Bhargav Kale","doi":"10.1007/s10468-024-10285-7","DOIUrl":"10.1007/s10468-024-10285-7","url":null,"abstract":"<div><p>We show that the order type of the simplest version of a hammock for string algebras lies in the class of <i>finite description</i> linear orders–the smallest class of linear orders containing <span>(textbf{0})</span>, <span>(textbf{1})</span>, and that is closed under isomorphisms, finite order sum, anti-lexicographic product with <span>(omega )</span> and <span>(omega ^*)</span>, and shuffle of finite subsets–using condensation (localization) of linear orders as a tool. We also introduce two finite subsets of the set of bands and use them to describe the location of left <span>(mathbb {N})</span>-strings in the completion of hammocks.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 5","pages":"1869 - 1908"},"PeriodicalIF":0.5,"publicationDate":"2024-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Translation Hopf Algebras and Hopf Heaps","authors":"Tomasz Brzeziński, Małgorzata Hryniewicka","doi":"10.1007/s10468-024-10283-9","DOIUrl":"10.1007/s10468-024-10283-9","url":null,"abstract":"<div><p>To every Hopf heap or quantum cotorsor of Grunspan a Hopf algebra of translations is associated. This translation Hopf algebra acts on the Hopf heap making it a Hopf-Galois co-object. Conversely, any Hopf-Galois co-object has the natural structure of a Hopf heap with the translation Hopf algebra isomorphic to the acting Hopf algebra. It is then shown that this assignment establishes an equivalence between categories of Hopf heaps and Hopf-Galois co-objects.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 5","pages":"1805 - 1819"},"PeriodicalIF":0.5,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10468-024-10283-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Hopf Algebras with the Dual Chevalley Property of Finite Corepresentation Type","authors":"Jing Yu, Kangqiao Li, Gongxiang Liu","doi":"10.1007/s10468-024-10284-8","DOIUrl":"10.1007/s10468-024-10284-8","url":null,"abstract":"<div><p>Let <i>H</i> be a finite-dimensional Hopf algebra over an algebraically closed field <span>(Bbbk )</span> with the dual Chevalley property. We prove that <i>H</i> is of finite corepresentation type if and only if it is coNakayama, if and only if the link quiver <span>(textrm{Q}(H))</span> of <i>H</i> is a disjoint union of basic cycles, if and only if the link-indecomposable component <span>(H_{(1)})</span> containing <span>(Bbbk 1)</span> is a pointed Hopf algebra and the link quiver of <span>(H_{(1)})</span> is a basic cycle.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 5","pages":"1821 - 1867"},"PeriodicalIF":0.5,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantum Frobenius Splittings and Cluster Structures","authors":"Jinfeng Song","doi":"10.1007/s10468-024-10281-x","DOIUrl":"10.1007/s10468-024-10281-x","url":null,"abstract":"<div><p>We prove that the duals of the quantum Frobenius morphisms and their splittings by Lusztig are compatible with quantum cluster monomials. After specialization, we deduce that the canonical Frobenius splittings on flag varieties are compatible with cluster algebra structures on Schubert cells.</p></div>","PeriodicalId":50825,"journal":{"name":"Algebras and Representation Theory","volume":"27 5","pages":"1773 - 1797"},"PeriodicalIF":0.5,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141948726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}