Horospherical stacks and stacky coloured fans
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- by Sean Monahan;
- Trans. Amer. Math. Soc. 378 (2025), 1167-1214
- DOI: https://doi.org/10.1090/tran/9297
- Published electronically: December 27, 2024
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Abstract:
We introduce a combinatorial theory of horospherical stacks which is motivated by the work of Geraschenko and Satriano on toric stacks. A horospherical stack corresponds to a combinatorial object called a stacky coloured fan. We give many concrete examples, including a class of easy-to-draw examples called coloured fantastacks. The main results in this paper are combinatorial descriptions of horospherical stacks, the morphisms between them, their decolourations, and their good moduli spaces.References
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Bibliographic Information
- Sean Monahan
- Affiliation: Department of Pure Mathematics, University of Waterloo, 200 University Ave. W, Waterloo, Ontario, Canada
- ORCID: 0009-0008-3559-8336
- Email: sean.monahan@uwaterloo.ca
- Received by editor(s): June 22, 2023
- Received by editor(s) in revised form: June 20, 2024
- Published electronically: December 27, 2024
- Additional Notes: The author was supported by a PGS-D scholarship from the Natural Sciences and Engineering Research Council of Canada (reference number: PGSD3-558713-2021).
- © Copyright 2024 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 378 (2025), 1167-1214
- MSC (2020): Primary 14M27, 14A20, 05E14; Secondary 14M17, 14M15, 14M25
- DOI: https://doi.org/10.1090/tran/9297