  We use the Perron-Frobenius Theorem to define, study and, in some sense,
classify special simple modules over arbitrary finite dimensional positively
based algebras. For group algebras of finite Weyl groups with respect to the
Kazhdan-Lusztig basis, this agrees with Lusztig's notion of a special module
introduced in [Lu1].

Representation Theory;Group Theory;Rings and Algebras