Characterization of some subgraphs of point-collinearity graphs of building geometries
نویسنده
چکیده
Let B be a building over a type set I . Suppose J ⊆ I meets every connected component of the diagram of B and let (P,L) be the point-line truncation of the J -Grassmann geometry of B. We present a theorem that allows one to identify shadows of apartments of residues of B in the point-collinearity graph of (P,L). Also, other results related to shadows of apartments of residues and shadows of residues are presented, including a proof of the fact that the shadow of every residue of B is a convex subspace of (P,L). c © 2007 Published by Elsevier Ltd
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 28 شماره
صفحات -
تاریخ انتشار 2007