Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-23T19:53:34.326Z Has data issue: false hasContentIssue false

A GRAPHICAL CALCULUS FOR 2-BLOCK SPALTENSTEIN VARIETIES

Published online by Cambridge University Press:  29 March 2012

GISA SCHÄFER*
Affiliation:
University of Bonn, Mathematikzentrum, Endenicher Allee 60, 53115 Bonn, Germany e-mail: gschaefe@uni-bonn.de
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We generalise statements known about Springer fibres associated to nilpotents with two Jordan blocks to Spaltenstein varieties. We study the geometry of generalised irreducible components (i.e. Bialynicki-Birula cells) and their pairwise intersections. In particular, we develop a graphical calculus that encodes their structure as iterated fibre bundles with ℂℙ1 as base spaces, and compute their cohomology. At the end, we present a connection with coloured cobordisms generalising the construction of Khovanov (M. Khovanov, A categorification of the Jones polynomial, Duke Math. J. 101(3) (2000), 359–426) and Stroppel (C. Stroppel, Parabolic category O, perverse sheaves on Grassmannians, Springer fibres and Khovanov homology, Compositio Mathematica145(4) (2009), 954–992).

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 2012

References

REFERENCES

1.Brundan, J., Symmetric functions, parabolic category ℴ, and the Springer fiber, Duke Math. J. 143 (1) (2008), 4179.Google Scholar
2.Brundan, J. and Stroppel, C., Highest weight categories arising from Khovanov's diagram algebra III: Category O, Represent. Theory. 15 (2011), 170243.Google Scholar
3.Enright, T. J. and Shelton, B., Categories of highest weight modules: applications to classical Hermitian symmetric pairs, Mem. Amer. Math. Soc. 367 (1987), MR 888703 (88f:22052).Google Scholar
4.Fresse, L., On the singularity of some special components of Springer fibers, J. Lie Theory 21 (1) (2011), 205242.Google Scholar
5.Fresse, L. and Melnikov, A., On the singularity of the irreducible components of a Springer fiber in sln, Sel. Math. (New Series) 16 (2010), 126.Google Scholar
6.Fung, F. Y. C., On the topology of components of some Springer fibers and their relation to Kazhdan–Lusztig theory, Adv. Math. 178 (2) (2003), 244276.Google Scholar
7.Gunning, R. C. and Rossi, H., Analytic functions of several complex variables (Prentice-Hall, Englewood Cliffs, NJ, 1965).Google Scholar
8.Hartshorne, R., Algebraic geometry, Graduate texts in mathematics 52 (Springer, Berlin, Germany, 1977).Google Scholar
9.Hatcher, A., Algebraic topology (Cambridge University Press, Cambridge, UK, 2003).Google Scholar
10.Humphreys, J. E., Linear algebraic groups, Graduate texts in mathematics 21 (Springer, Berlin, Germany, 1975).Google Scholar
11.Khovanov, M., A categorification of the Jones polynomial, Duke Math. J. 101 (3) (2000), 359426.CrossRefGoogle Scholar
12.Kock, J., Frobenius algebras and 2d topological quantum field theories, vol. 59 (Cambridge University Press, Cambridge, UK, 2004).Google Scholar
13.McCleary, J., User's guide to spectral sequences, Mathematics lecture series 12 (Publish or Perish, Wilmington, DE, 1985).Google Scholar
14.Schäfer, G., Monoidal 2-functors and spaltenstein varieties, Diploma Thesis (University of Bonn, Bonn, Germany, 2010). Available at http://www.math.uni-bonn.de/people/stroppel/Diplomathesis_GisaSchaefer.pdf.Google Scholar
15.Serre, J. P., Géométrie analytique et géométrie algébrique, Ann. de l'Institut Fourier 6 (1955), 142.Google Scholar
16.Spaltenstein, N., The fixed point set of a unipotent transformation on the flag manifold, Proc. Koninklijke Nederlandse Akademie van Wetenschappen, 79 (1976), 452456.Google Scholar
17.Spaltenstein, N., Classes unipotentes et sous-groupes de Borel (Springer, Berlin, Germany, 1982).Google Scholar
18.Spanier, E. H., Algebraic topology (McGraw-Hill, New York, 1966).Google Scholar
19.Stroppel, C., Parabolic category ℴ, perverse sheaves on Grassmannians, Springer fibres and Khovanov homology, Compositio Mathematica 145 (04) (2009), 954992.Google Scholar
20.Stroppel, C. and Webster, B., 2-block Springer fibers: convolution algebras and coherent sheaves, Arxiv preprint arXiv:0802.1943 (2008), to appear in Comm. Math. Helv.Google Scholar
21.Vargas, J. A., Fixed points under the action of unipotent elements of SLn in the flag variety, Boletin Sociedad Matemática Mexicana 24 (1979), 114.Google Scholar