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In his letter Peter Webb writes:

On the topic of representation theory within GAP, I have the impression

that this side of things has been somewhat neglected so far. The meataxe

is implemented, but I have other goals in mind to do with creating software

to complement this. For example, the meataxe would not be so good for

analyzing the structure of modules for p-groups in characteristic p, but

algorithms based upon the computation of fixed points are very effective in

this situation. It is a long-term project for me to expand what software

I have, and to put it into a publicly acceptable state. Right now, for

example, it does not properly conform to the object-oriented style of GAP,

and it is not adequately tested. At this point I would be happy to hear of

others writing similar software (some I already know of). My general aim

is to have a package which computes Loewy series reasonably, will extract

a quotient in the Loewy series of a p-group as a representation of its

normalizer in a larger group (for example), will compute relative traces

between modules of fixed points, and such similar things.

We agree. While character theory (and hence ordinary representation

theory) is rather well represented in GAP, working with modular

representations is not yet. Note however that there is a link to the

MOC system for working with modular characters provided in GAP (see

section 42.46 ff, p.679 of the manual). We do intend to extend

facilities for working in modular representation theory and we will

welcome cooperation with others who have already implemented routines

or are implementing routines in this field. We will contact Peter

Webb directly but also ask others who are interested to contact us,

e.g. Klaus Lux or Herbert Pahlings (lux@math.rwth-aachen.de ,

pahlings@math.rwth-aachen.de) and we hope that eventually we will be

able to provide a good package.

Joachim Neubueser

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