Modules with Demazure Flags and Character Formulae

In this paper we study a family of finite-dimensional graded representations of the current algebra of sl₂ which are indexed by partitions. We show that these representations admit a flag where the successive quotients are Demazure modules which occur in a level ℓ-integrable module for A₁¹ as long a...

Full description

Saved in:
Bibliographic Details
Published in:Symmetry, Integrability and Geometry: Methods and Applications
Date:2014
Main Authors: Chari, V., Schneider, L., Shereen, P., Wand, J.
Format: Article
Language:English
Published: Інститут математики НАН України 2014
Online Access:https://nasplib.isofts.kiev.ua/handle/123456789/146820
Tags: Add Tag
No Tags, Be the first to tag this record!
Journal Title:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Cite this:Modules with Demazure Flags and Character Formulae / V. Chari, L. Schneider, P. Shereen, J. Wand // Symmetry, Integrability and Geometry: Methods and Applications. — 2014. — Т. 10. — Бібліогр.: 16 назв. — англ.

Institution

Digital Library of Periodicals of National Academy of Sciences of Ukraine
id nasplib_isofts_kiev_ua-123456789-146820
record_format dspace
spelling Chari, V.
Schneider, L.
Shereen, P.
Wand, J.
2019-02-11T16:22:41Z
2019-02-11T16:22:41Z
2014
Modules with Demazure Flags and Character Formulae / V. Chari, L. Schneider, P. Shereen, J. Wand // Symmetry, Integrability and Geometry: Methods and Applications. — 2014. — Т. 10. — Бібліогр.: 16 назв. — англ.
1815-0659
2010 Mathematics Subject Classification: 06B15 ; 05E10; 14H42
DOI:10.3842/SIGMA.2014.032
https://nasplib.isofts.kiev.ua/handle/123456789/146820
In this paper we study a family of finite-dimensional graded representations of the current algebra of sl₂ which are indexed by partitions. We show that these representations admit a flag where the successive quotients are Demazure modules which occur in a level ℓ-integrable module for A₁¹ as long as ℓ is large. We associate to each partition and to each ℓ an edge-labeled directed graph which allows us to describe in a combinatorial way the graded multiplicity of a given level ℓ-Demazure module in the filtration. In the special case of the partition 1s and ℓ=2, we give a closed formula for the graded multiplicity of level two Demazure modules in a level one Demazure module. As an application, we use our result along with the results of Naoi and Lenart et al., to give the character of a g-stable level one Demazure module associated to B¹n as an explicit combination of suitably specialized Macdonald polynomials. In the case of sl₂, we also study the filtration of the level two Demazure module by level three Demazure modules and compute the numerical filtration multiplicities and show that the graded multiplicites are related to (variants of) partial theta series.
This paper is a contribution to the Special Issue in honor of Anatol Kirillov and Tetsuji Miwa. The full collection is available at http://www.emis.de/journals/SIGMA/InfiniteAnalysis2013.html. The authors thank S. Viswanath for discussions regarding the graph H`(ξ) and for drawing their attention to the connection of the results of Subsection 3.10 to partial theta series. The first and third authors acknowledge the hospitality and excellent working conditions at the Institute of Mathematical Sciences, Chennai, India where part of this work was done. They also thank the referees of the paper for their careful reading of the paper and for their many valuable comments. The first author was partially supported by DMS-0901253 and DMS-1303052.
en
Інститут математики НАН України
Symmetry, Integrability and Geometry: Methods and Applications
Modules with Demazure Flags and Character Formulae
Article
published earlier
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
title Modules with Demazure Flags and Character Formulae
spellingShingle Modules with Demazure Flags and Character Formulae
Chari, V.
Schneider, L.
Shereen, P.
Wand, J.
title_short Modules with Demazure Flags and Character Formulae
title_full Modules with Demazure Flags and Character Formulae
title_fullStr Modules with Demazure Flags and Character Formulae
title_full_unstemmed Modules with Demazure Flags and Character Formulae
title_sort modules with demazure flags and character formulae
author Chari, V.
Schneider, L.
Shereen, P.
Wand, J.
author_facet Chari, V.
Schneider, L.
Shereen, P.
Wand, J.
publishDate 2014
language English
container_title Symmetry, Integrability and Geometry: Methods and Applications
publisher Інститут математики НАН України
format Article
description In this paper we study a family of finite-dimensional graded representations of the current algebra of sl₂ which are indexed by partitions. We show that these representations admit a flag where the successive quotients are Demazure modules which occur in a level ℓ-integrable module for A₁¹ as long as ℓ is large. We associate to each partition and to each ℓ an edge-labeled directed graph which allows us to describe in a combinatorial way the graded multiplicity of a given level ℓ-Demazure module in the filtration. In the special case of the partition 1s and ℓ=2, we give a closed formula for the graded multiplicity of level two Demazure modules in a level one Demazure module. As an application, we use our result along with the results of Naoi and Lenart et al., to give the character of a g-stable level one Demazure module associated to B¹n as an explicit combination of suitably specialized Macdonald polynomials. In the case of sl₂, we also study the filtration of the level two Demazure module by level three Demazure modules and compute the numerical filtration multiplicities and show that the graded multiplicites are related to (variants of) partial theta series.
issn 1815-0659
url https://nasplib.isofts.kiev.ua/handle/123456789/146820
citation_txt Modules with Demazure Flags and Character Formulae / V. Chari, L. Schneider, P. Shereen, J. Wand // Symmetry, Integrability and Geometry: Methods and Applications. — 2014. — Т. 10. — Бібліогр.: 16 назв. — англ.
work_keys_str_mv AT chariv moduleswithdemazureflagsandcharacterformulae
AT schneiderl moduleswithdemazureflagsandcharacterformulae
AT shereenp moduleswithdemazureflagsandcharacterformulae
AT wandj moduleswithdemazureflagsandcharacterformulae
first_indexed 2025-11-29T10:46:14Z
last_indexed 2025-11-29T10:46:14Z
_version_ 1850854801140613120