Stephen R Doty

• Email: doty AT math DOT luc DOT edu, sdoty AT luc DOT edu

• Mailing address:

  Department of Mathematics and Statistics, Loyola University Chicago, Chicago, IL 60660 USA

  (Anything important should be sent by email)

• algebraic groups
• finite-dimensional algebras
• groups of Lie type
• Lie algebras
• quantum groups.

Some specialized topics of interest include:

• Schur-Weyl duality
• Schur algebras
• Hecke algebras
• quasihereditary algebras
• cellular algebras
• diagram algebras
• quantized enveloping algebras.

My preprints on the arXiv.

• HTML list
• Errata
• ORCID page
• Google Scholar page
• Math Reviews (login required)
• zbMATH Open

• Currently: Professor Emeritus, Loyola University Chicago
• 1994-2020: Professor, Loyola University Chicago
• 1987-1994: Assistant and Associate Professor, Loyola University Chicago
• 1985-1987: Kenna Assistant Professor, University of Note Dame
• 1982-1985: Acting Assistant Professor, University of Washington
• 1982: PhD, Mathematics, University of Notre Dame (Advisor: W J Wong)

A GAP package supporting computations with Weyl modules and simple modules for a given simply-connected simple algebraic group in positive characteristic. The package computes simple characters, decomposition numbers, and structural information. The package also has some (limited) support for Schur algebras and symmetric groups. The latest version is Version 2.1.

• Latest release: package website

• Version 2.0: GitHub

• Version 1.1: GAP-files, User-manual (bug fix; manual didn’t change)

• Version 1.0: GAP-files, User-manual

• Version 0.5: GAP-files, User-manual

Instructions for Versions before 2.0 only!

To try the software, download the GAP-files (a zip archive) and unpack it somewhere. It should unpack into three files (weyl.g, weylmod.gd, and weylmod.gi). From the same folder where you unpacked those files, initiate GAP by typing:

$ gap weyl.g

in a command shell. This will load the package into GAP’s memory, and you should now be able to test the commands. Alternatively, you can start a GAP session as usual and then load the package by typing the GAP command:

gap> Read( "weyl.g" );

if you initiated the GAP session from the same folder containing the file “weyl.g”. If not, you will need to tell GAP what path to use or specify a pathname on the Read command (and perhaps edit the file “weyl.g” to contain correct pathnames as well).