On affine Weyl group elements of positive Coxeter type
Abstract: We introduce a class of elements of the Iwahori-Weyl group of a reductive group that we call positive Coxeter elements. This class consists of elements which are linked to partial Coxeter elements in the finite Weyl group in a certain canonical way, extending the more restrictive notion of finite Coxeter part previously introduced by He-Nie-Yu. We show that the affine Deligne-Lusztig varieties associated with such elements have a very simple and explicitly described geometric structure. Conversely, we explain how some of these geometric properties can be used to characterize elements of positive Coxeter type.
- Francesco Brenti, Sergey Fomin and Alexander Postnikov “Mixed Bruhat Operators and Yang-Baxter Equations for Weyl Groups” In International Mathematics Research Notices 8, 1998, pp. 419–441
- R. Carter “Conjugacy classes in the Weyl group” In Seminar on Algebraic Groups and Related Finite Groups: Held at The Institute for Advanced Study, Princeton/NJ, 1968/69 Berlin, Germany: Springer, 2006, pp. 297–318 DOI: 10.1007/BFb0081548
- Ching-Li Chai “Newton Polygons as Lattice Points” In American Journal of Mathematics 122.5 Johns Hopkins University Press, 2000, pp. 967–990 URL: http://www.jstor.org/stable/25099024
- Vinay V. Deodhar “On the root system of a coxeter group” In Comm. Algebra 10.6 Taylor & Francis, 1982, pp. 611–630 DOI: 10.1080/00927878208822738
- “Affine Deligne-Lusztig varieties in affine flag varieties” In Compositio Mathematica 146.5, 2010, pp. 1339–1382 DOI: 10.1112/S0010437X10004823
- “Dimension of affine Deligne-Lusztig varieties in affine flag varieties” In Documenta Mathematica 15, 2010 URL: https://www.researchgate.net/publication/45923146_Dimension_of_affine_Deligne-Lusztig_varieties_in_affine_flag_varieties
- Ulrich Görtz, Xuhua He and Sian Nie “P𝑃Pitalic_P-alcoves and nonemptiness of affine Deligne-Lusztig varieties” In Annales Scientifiques de l’Ecole Normale Superieure 48, 2015 DOI: 10.24033/asens.2254
- Ulrich Görtz, Xuhua He and Sian Nie “Fully Hodge–Newton Decomposable Shimura Varieties” In Peking Math. J. 2.2 Springer Singapore, 2019, pp. 99–154 DOI: 10.1007/s42543-019-00013-2
- “Appendix: On parahoric subgroups” In Advances in Mathematics 219.1, 2008, pp. 188–198 URL: https://www.academia.edu/21123499/On_parahoric_subgroups
- “Irreducible components of minuscule affine Deligne–Lusztig varieties” In Algebra & Number Theory 12.7 Mathematical Sciences Publishers, 2018, pp. 1611–1634 DOI: 10.2140/ant.2018.12.1611
- Xuhua He “Geometric and homological properties of affine Deligne-Lusztig varieties” In Annals of Mathematics 179.1 Princeton Universitythe Institute for Advanced Study, 2014, pp. 367–404 DOI: 10.4007/annals.2014.179.1.6
- Xuhua He “Hecke algebras and p𝑝pitalic_p-adic groups” In Current Developments in Mathematics 2015.1 International Press of Boston, Inc., 2015 DOI: 10.4310/CDM.2015.v2015.n1.a3
- Xuhua He “Affine Deligne-Lusztig varieties associated with generic Newton points”, 2021 arXiv: https://arxiv.org/abs/2107.14461v1
- Xuhua He “Cordial elements and dimensions of affine Deligne–Lusztig varieties” In Forum of Mathematics, Pi 9 Cambridge University Press, 2021 DOI: 10.1017/fmp.2021.10
- “A generalization of Steinberg’s cross section” In J. Amer. Math. Soc. 25.3, 2012, pp. 739–757 DOI: 10.1090/S0894-0347-2012-00728-0
- “Minimal length elements of extended affine Weyl groups” In Compositio Mathematica 150.11 London Mathematical Society, 2014, pp. 1903–1927 DOI: 10.1112/S0010437X14007349
- “P𝑃Pitalic_P-alcoves, parabolic subalgebras and cocenters of affine Hecke algebras” In Sel. Math. New. Ser. 21.3 Springer Basel, 2015, pp. 995–1019 DOI: 10.1007/s00029-014-0170-x
- Xuhua He, Sian Nie and Qingchao Yu “Affine Deligne–Lusztig varieties with finite Coxeter parts” arXiv, 2022 DOI: 10.48550/ARXIV.2208.14058
- “Elements with finite Coxeter part in an affine Weyl group” In J. Algebra 372 Academic Press, 2012, pp. 204–210 DOI: 10.1016/j.jalgebra.2012.09.017
- Xuhua He, Rong Zhou and Yihang Zhu “Stabilizers of irreducible components of affine Deligne–Lusztig varieties” In arXiv, 2021 DOI: 10.48550/arXiv.2109.02594
- Robert E. Kottwitz “Isocrystals with additional structure” In Compositio Mathematica 56.2 Martinus Nijhoff Publishers, 1985, pp. 201–220 URL: http://eudml.org/doc/89735
- Robert E. Kottwitz “Isocrystals with additional structure. II” In Compositio Mathematica 109.3 London Mathematical Society, 1997, pp. 255–339 DOI: 10.1023/A:1000102604688
- “A Uniform Model for Kirillov–Reshetikhin Crystals I: Lifting the Parabolic Quantum Bruhat Graph” In International Mathematics Research Notices 2015.7 Oxford Academic, 2015, pp. 1848–1901 DOI: 10.1093/imrn/rnt263
- “Induced Unipotent Classes” In J. London Math. Soc. s2-19.1 John Wiley & Sons, Ltd, 1979, pp. 41–52 DOI: 10.1112/jlms/s2-19.1.41
- Timothée Marquis “Structure of conjugacy classes in Coxeter groups” In arXiv, 2020 DOI: 10.48550/arXiv.2012.11015
- “Generic Newton points and the Newton poset in Iwahori-double cosets” In Forum of Mathematics, Sigma 8 Cambridge University Press, 2020 DOI: 10.1017/fms.2020.46
- Sian Nie “Steinberg’s cross-section of Newton strata” In arXiv, 2023 DOI: 10.48550/arXiv.2307.12521
- Michael Rapoport “A Guide to the reduction modulo p𝑝pitalic_p of Shimura varieties” In Astérisque, 2002 URL: https://www.researchgate.net/publication/2102268_A_Guide_to_the_reduction_modulo_P_of_Shimura_varieties
- Felix Schremmer “Affine Bruhat order and Demazure products”, 2022 DOI: 10.48550/arXiv.2205.02633
- Felix Schremmer “Generic Newton points and cordial elements”, 2022 DOI: 10.48550/arXiv.2205.02039
- Felix Schremmer “Newton Strata in Levi Subgroups”, 2023 arXiv:2305.00683 [math.AG]
- David E. Speyer “Powers of Coxeter Elements in Infinite Groups Are Reduced” In Proceedings of the American Mathematical Society 137.4 American Mathematical Society, 2009, pp. 1295–1302 URL: http://www.jstor.org/stable/20535863
- T.A. Springer “Regular elements of finite reflection groups” In Invent. Math. 25.2 Springer-Verlag, 1974, pp. 159–198 DOI: 10.1007/BF01390173
- Jacques Tits “Reductive groups over local fields” In Automorphic Forms, Representations and ℒℒ\mathcal{L}caligraphic_L-Functions, Part 1 33.1 American Mathematical Society, 1979 DOI: 10.1090/pspum/033.1
- Eva Viehmann “Truncations of level 1111 of elements in the loop group of a reductive group” In Annals of Mathematics 179.3 Princeton Universitythe Institute for Advanced Study, 2014, pp. 1009–1040 DOI: 10.4007/annals.2014.179.3.3
- Eva Viehmann “Minimal Newton Strata in Iwahori Double Cosets” In International Mathematics Research Notices 2021.7 Oxford Academic, 2021, pp. 5349–5365 DOI: 10.1093/imrn/rnz351
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