The VIGRE Algebra Group was led by David
Benson, Brian Boe, and Daniel Nakano. The other members
of the group are
Faculty:
Leonard Chastkofsky
Jerome Jungster
Postdocs:
Nadia Mazza
Jonathan Kujawa
Graduate Students:
Irfan Bagci
Phil Bergonio
Kenyon J. Platt
Stephen Winburn
Caroline Wright
The main goal of the VIGRE Algebra Seminar this term was to to study
support varieties for modules
over the symmetric group. Support varieties were developed 25 years ago
in the pioneering work of
Alperin and Carlson. Since their introduction, these varieties have
played a central role in the cohomology
theory of finite groups and restricted Lie algebras. Although these
varieties are easy to define once the
finite generation of cohomology is established, they are often very
difficult to compute. One of the main
objectives of this project is to make significant progress in computing
these varieties for important
classes of modules.
At the start of the semester Benson presented four lectures on the
elementary properties of the cohomological
variety theory. This was followed by three lectures by Kujawa on
symmetric group representations. Nakano presented
two lectures on the computation of the support varieties for Young and
permutation modules (recent results with
David Hemmer). During the last four weeks of the term Benson led the
group in making explicit computations of
varieties for symmetric groups. We discovered formulas for
certain Specht modules and have started to compute
the supports for Specht modules for the symmetric group on d letters
when d<p^2 (where the characterstic of the
underlying field is p). We are optimistic this case will be solved near
the beginning of next semester.
Several students in the group, Bergonio, Platt and Wright, finished up
computations on the support varieties of
Weyl modules over bad primes. This effort was initiated and led over
the summer by Chastkofsky. Boe and Nakano have
compiled the data and have written up the results. A preprint (the
third paper written by our group) is now available.
The first VIGRE Algebra Group paper has now appeared: J. Algebra, 280
(2004), 719-737 and the second
VIGRE Algebra Group paper will appear in the new Journal of Algebra
section devoted to computational algebra.
Bagci and Winburn are new members to our group. They are making good
progress with the material and we are optimistic
they will contribute further in the spring.