The geometry of conjugation in affine Coxeter groups

We develop precise geometric descriptions of the conjugacy class [x] and coconjugation set C(x,x')={y∈W̄|yxy−1=x'} for all elements x,x' of any affine Coxeter group W̄. The centralizer of x in ̄W is the special case C(x,x). The key structure in our description of the conjugacy class [...

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Bibliographic Details
Main Authors: Milićević, Elizabeth (Author) , Schwer, Petra (Author) , Thomas, Anne (Author)
Format: Article (Journal)
Language:English
Published: 2025
In: International journal of algebra and computation
Year: 2025, Volume: 35, Issue: 03, Pages: 403-465
ISSN:0218-1967
DOI:10.1142/S0218196725500109
Online Access:Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1142/S0218196725500109
Verlag, lizenzpflichtig, Volltext: https://www.worldscientific.com/doi/10.1142/S0218196725500109
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Author Notes:Elizabeth Milićević, Petra Schwer, and Anne Thomas
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Summary:We develop precise geometric descriptions of the conjugacy class [x] and coconjugation set C(x,x')={y∈W̄|yxy−1=x'} for all elements x,x' of any affine Coxeter group W̄. The centralizer of x in ̄W is the special case C(x,x). The key structure in our description of the conjugacy class [x] is the mod-set ModW̄(w)=(w−I)R∨, where w is the finite part of x and R∨ is the coroot lattice. The set C(x,x') is then described by ModW̄(w') together with the fix-set of w', where w' is the finite part of x'. For any element w of the associated finite Weyl group W, the mod-set of w is contained in the classical move-set Mov(w)=Im(w−I). We prove that the rank of ModW̄(w) equals the dimension of Mov(w) and investigate type-by-type the surprisingly subtle structure of Mod W̄(w).
Item Description:Gesehen am 02.10.2025
Physical Description:Online Resource
ISSN:0218-1967
DOI:10.1142/S0218196725500109