The Symmetric Group Action on Rank-selected Posets of Injective Words

Order - Tập 35 - Trang 47-56 - 2016
Christos A. Athanasiadis1
1Department of Mathematics, National and Kapodistrian University of Athens, Athens, Greece

Tóm tắt

The symmetric group $\mathfrak {S}_{n}$ acts naturally on the poset of injective words over the alphabet {1, 2,…,n}. The induced representation on the homology of this poset has been computed by Reiner and Webb. We generalize their result by computing the representation of $\mathfrak {S}_{n}$ on the homology of all rank-selected subposets, in the sense of Stanley. A further generalization to the poset of r-colored injective words is given.

Tài liệu tham khảo

Adin, R.M., Athanasiadis, C.A., Elizalde, S., Roichman, Y.: Character formulas and descents for the hyperoctahedral group. arXiv:1504.01283 Björner, A., Wachs, M.: On lexicographically shellable posets. Trans. Amer. Math. Soc. 277, 323–341 (1983) Church, T.: Homological stability for configuration spaces of manifolds. Invent. Math. 188, 465–504 (2012) Church, T., Farb, B.: Representation theory and homological stability. Adv. Math. 245, 250–314 (2013) Désarménien, J.: Une autre interprétation du nombre de dérangements. Sém.Lothar. Combin. 8 (1984). Article B08b, 6pp (electronic) Désarménien, J., Wachs, M.: Descentes de dérangements et mot circulaires. Sém. Lothar. Combin. 19 (1988). Article B19a, 9pp (electronic) Désarménien, J., Wachs, M.: Descent classes of permutations with a given number of fixed points. J. Combin. Theory Series A 64, 311–328 (1993) Dieker, A.B., Saliola, F.: Spectral analysis of random-to-random Markov chains. arXiv:1509.08580 Farmer, F.D.: Cellular homology for posets. Math. Japon. 23, 607–613 (1979) Hanlon, P., Hersh, P.: A Hodge decomposition for the complex of injective words. Pac. J. Math. 214, 109–125 (2004) Hersh, P., Reiner, V.: Representation stability for cohomology of configuration spaces in \({\mathbb R}^{d}\), Int. Math. Res. Notices (to appear) Jonsson, J., Welker, V.: Complexes of injective words and their commutation classes. Pac. J. Math. 243, 313–329 (2009) Kallipoliti, M., Kubitzke, M.: A poset fiber theorem for doubly Cohen-Macaulay posets and its applications. Ann. Comb. 17, 711–731 (2013) Reiner, V., Webb, P.: The combinatorics of the bar resolution in group cohomology. J. Pure Appl. Algebra 190, 291–327 (2004) Sagan, B.E.: The Symmetric Group: Representations, Combinatorial Algorithms and Symmetric Functions, 2nd edn, Graduate Texts in Mathematics, vol. 203. Springer (2001) Stanley, R.P.: Some aspects of groups acting on finite posets. J. Combin. Theory Series A 32, 132–161 (1982) Stanley, R.P.: Combinatorics and Commutative Algebra, 2nd edn. Birkhäuser, Basel (1996) Stanley, R.P.: Enumerative Combinatorics, vol. 1, 2nd edn, Cambridge Studies in Advanced Mathematics, vol. 49. Cambridge University Press, Cambridge (2011) Stanley, R.P.: Enumerative Combinatorics, vol. 2, Cambridge Studies in Advanced Mathematics, vol. 62. Cambridge University Press, Cambridge (1999) Wachs, M.: Poset Topology: Tools and Applications. In: Miller, E., Reiner, V., Sturmfels, B. (eds.) IAS/Park City Mathematics Series, vol. 13, pp. 497–615. Amer. Math. Society, Providence, RI (2007)