A proof of Lusztig's connectedness conjecture in finite type

Primarily AI-generated textHuman understanding: no partsmath.RT — Representation Theorymath.CO — Combinatorics

Contributed by Qiyue Tang ↗

Version 1 / Nov 13, 2026 / CC BY 4.0

Abstract

We prove that every equal-parameter Kazhdan–Lusztig left cell in a finite Weyl group is connected by simple left multiplications.

Author comments: I am posting this manuscript to share the mathematical results themselves. In doing so, I do not seek to assert ownership of the results or claim priority. I welcome anyone interested in checking the arguments or preparing a finished account, and I believe the eventual scholarly credit should go to those who undertake that work.

Provenance statement

GPT-6-Pro was used in a broader investigation of Lusztig's connectedness conjecture over twelve research sessions, with approximately 88 hours of documented research-session time in total. This paper presents the finite-type part of that investigation. GPT-6-Pro was also used to review the mathematical arguments and edit the manuscript. A review by Rethlas-OSV will be added in a subsequent update.

References

  1. D. Garfinkle, On the classification of primitive ideals for complex classical Lie algebras, I , Compositio Math. 75 (1990), 135--169.
  2. D. Garfinkle, On the classification of primitive ideals for complex classical Lie algebras, II , Compositio Math. 81 (1992), 307--336.
  3. D. Garfinkle, On the classification of primitive ideals for complex classical Lie algebras, III , Compositio Math. 88 (1993), 187--234.
  4. D. Garfinkle Johnson, Edge transport from parabolic subgroups of type D4D_4 , arXiv:1907.09717v2 (https://arxiv.org/abs/1907.09717v2), 2019.arXiv
  5. D. Garfinkle and D. A. Vogan, Jr., On the structure of Kazhdan--Lusztig cells for branched Dynkin diagrams , J. Algebra 153 (1992), 91--120.
  6. M. Geck, Relative Kazhdan--Lusztig cells , Represent. Theory 10 (2006), 481--524.
  7. M. Geck, On the Kazhdan--Lusztig order on cells and families , Comment. Math. Helv. 87 (2012), 905--927.
  8. M. Geck and A. Halls, On the Kazhdan--Lusztig cells in type E8E_8 , Math. Comp. 84 (2015), no. 296, 3029--3049.
  9. T. Pietraho, W. M. McGovern and D. Garfinkle, On the classification of primitive ideals for complex classical Lie algebras, IV , arXiv:2309.02363v3 (https://arxiv.org/abs/2309.02363v3), 2026; first version, 2023; version 2 (https://arxiv.org/abs/2309.02363v2), September 25, 2023.arXiv
  10. J. E. Humphreys, Reflection groups and Coxeter groups , Cambridge Studies in Advanced Mathematics, vol. 29, Cambridge University Press, Cambridge, 1990.
Show all 19 referencesShow fewer references
  1. L. T. Jensen, The ABC of pp-cells , Selecta Math. (N.S.) 26 (2020), no. 2, Paper No. 28, 46 pp.; arXiv:1901.02323v2 (https://arxiv.org/abs/1901.02323v2), 2019.arXiv
  2. D. Kazhdan and G. Lusztig, Representations of Coxeter groups and Hecke algebras , Invent. Math. 53 (1979), 165--184.
  3. G. Lusztig, contribution to Open problems in algebraic groups , R. Hotta and N. Kawanaka (eds.), problems from the Taniguchi Symposium on Algebraic Groups and Their Representations, Katata, August 29--September 3, 1983, p. 14.
  4. G. Lusztig, Characters of reductive groups over a finite field , Annals of Mathematics Studies, vol. 107, Princeton University Press, Princeton, NJ, 1984.
  5. W. M. McGovern, Left cells and domino tableaux in classical Weyl groups , Compositio Math. 101 (1996), 77--98.
  6. Q.-q. Mi and J.-y. Shi, Left-connectedness of left cells in the Weyl group of type E6E_6 , J. East China Normal Univ. Natur. Sci. Ed. 2013 (2013), no. 1, 76--90.
  7. J.-y. Shi, Coxeter elements and Kazhdan--Lusztig cells , J. Algebra 250 (2002), 229--251.
  8. J.-y. Shi, Left cells containing a fully commutative element , J. Combin. Theory Ser. A 113 (2006), 556--565.
  9. J.-y. Shi, Left-connectedness of some left cells in certain Coxeter groups of simply-laced type , J. Algebra 319 (2008), 2410--2433.

Version history

  1. v1 · 30 pagesSubmitted by Qiyue TangI am posting this manuscript to share the mathematical results themselves. In doing so, I do not seek to assert ownership of the results or claim priority. I welcome anyone interested in checking the arguments or preparing a finished account, and I believe the eventual scholarly credit should go to those who undertake that work.CurrentNov 12, 2026