Simplicity of Modules given by Oppositeness Relations in Spherical Buildings
نویسنده
چکیده
Oppositeness graphs of a spherical building are generalizations of the classical Kneser graphs. Recently Brouwer [1] has shown that the square of each eigenvalue of the adjacency matrix of an oppositeness graph is a power of q, for buildings of finite groups of Lie type defined over Fq. Here we show that the incidence modules are simple. The essential part of the proof is a result of Carter and Lusztig [2].
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تاریخ انتشار 2009