Abstract
The homology of a Garside monoid, thus of a Garside group, can be computed efficiently through the use of the order complex defined by Dehornoy and Lafont. We construct a categorical generalization of this complex and we give some computational techniques which are useful for reducing computing time. We then use this construction to complete results of Salvetti, Callegaro and Marin regarding the homology of exceptional complex braid groups. We most notably study the case of the Borchardt braid group \(B(G_{31})\) through its associated Garside category.
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Acknowledgements
The computational results for the braid groups of \(G_{24},G_{27},G_{29},G_{31},\) \(G_{33}\) and \(G_{34}\) were obtained using the MatriCS platform of the Université de Picardie Jules Verne in Amiens, France. I thank Étienne Piskorski, Laurent Renault and Jean-Baptiste Hoock for their help in using it. I also thank my PhD thesis advisor Ivan Marin for his precious help.
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Communicated by Vladimir Dotsenko.
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Garnier, O. Generalization of the Dehornoy–Lafont Order Complex to Categories: Application to Exceptional Braid Groups. Appl Categor Struct 32, 1 (2024). https://doi.org/10.1007/s10485-023-09757-6
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DOI: https://doi.org/10.1007/s10485-023-09757-6