Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Density of commensurators for uniform lattices of right-angled buildings   Let G be the automorphism group of a regular right-angled building X. The
"standard uniform lattice" \Gamma_0 in G is a canonical graph product of finite
groups, which acts discretely on X with quotient a chamber. We prove that the
commensurator of \Gamma_0 is dense in G. This result was also obtained by
Haglund. For our proof, we develop carefully a technique of "unfoldings" of
complexes of groups. We use unfoldings to construct a sequence of uniform
lattices \Gamma_n in G, each commensurable to \Gamma_0, and then apply the
theory of group actions on complexes of groups to the sequence \Gamma_n. As
further applications of unfoldings, we determine exactly when the group G is
nondiscrete, and we prove that G acts strongly transitively on X.

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The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
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The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio