Subspace arrangements, BNS invariants, and pure symmetric outer automorphisms of right-angled Artin groups

We introduce a homology theory for subspace arrangements, and use it to extract a new system of numerical invariants from the Bieri-Neumann-Strebel invariant of a group. We use these to characterize when the set of basis conjugating outer automorphisms (a.k.a. the pure symmetric outer automorphism g...

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Hlavní autoři: Day, M, Wad, R
Médium: Journal article
Vydáno: European Mathematical Society 2018
Popis
Shrnutí:We introduce a homology theory for subspace arrangements, and use it to extract a new system of numerical invariants from the Bieri-Neumann-Strebel invariant of a group. We use these to characterize when the set of basis conjugating outer automorphisms (a.k.a. the pure symmetric outer automorphism group) of a right-angled Artin group is itself a right-angled Artin group.