We obtain a combinatorial formula for the Miller–Morita–Mumford classes for the mapping class group of punctured surfaces and prove Witten’s conjecture that they are proportional to the dual to the Witten cycles. The proportionality constant is shown to be exactly as conjectured by Arbarello and Cornalba [J. Alg. Geom. 5 (1996) 705–749]. We also verify their conjectured formula for the leading coefficient of the polynomial expressing the Kontsevich cycles in terms of the Miller–Morita–Mumford classes.
Igusa, Kiyoshi  1
@article{10_2140_agt_2004_4_473,
author = {Igusa, Kiyoshi},
title = {Combinatorial {Miller{\textendash}Morita{\textendash}Mumford} classes and {Witten} cycles},
journal = {Algebraic and Geometric Topology},
pages = {473--520},
year = {2004},
volume = {4},
number = {1},
doi = {10.2140/agt.2004.4.473},
url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2004.4.473/}
}
TY - JOUR AU - Igusa, Kiyoshi TI - Combinatorial Miller–Morita–Mumford classes and Witten cycles JO - Algebraic and Geometric Topology PY - 2004 SP - 473 EP - 520 VL - 4 IS - 1 UR - http://geodesic.mathdoc.fr/articles/10.2140/agt.2004.4.473/ DO - 10.2140/agt.2004.4.473 ID - 10_2140_agt_2004_4_473 ER -
Igusa, Kiyoshi. Combinatorial Miller–Morita–Mumford classes and Witten cycles. Algebraic and Geometric Topology, Tome 4 (2004) no. 1, pp. 473-520. doi: 10.2140/agt.2004.4.473
[1] , , Combinatorial and algebro-geometric cohomology classes on the moduli spaces of curves, J. Algebraic Geom. 5 (1996) 705
[2] , , Moduli of graphs and automorphisms of free groups, Invent. Math. 84 (1986) 91
[3] , Stability of the homology of the mapping class groups of orientable surfaces, Ann. of Math. $(2)$ 121 (1985) 215
[4] , Graph cohomology and Kontsevich cycles, Topology 43 (2004) 1469
[5] , The space of framed functions, Trans. Amer. Math. Soc. 301 (1987) 431
[6] , A multiplication in cyclic homology, Trans. Amer. Math. Soc. 352 (2000) 209
[7] , Higher Franz–Reidemeister torsion, AMS/IP Studies in Advanced Mathematics 31, American Mathematical Society (2002)
[8] , , Increasing trees and Kontsevich cycles, Geom. Topol. 8 (2004) 969
[9] , , The Borel regulator map on pictures II: An example from Morse theory, $K$–Theory 7 (1993) 225
[10] , Intersection theory on the moduli space of curves and the matrix Airy function, Comm. Math. Phys. 147 (1992) 1
[11] , The homology of the mapping class group, J. Differential Geom. 24 (1986) 1
[12] , Combinatorial classes on $\overline{\mathcal{M}}_{g,n}$ are tautological, Int. Math. Res. Not. (2004) 2329
[13] , Characteristic classes of surface bundles, Bull. Amer. Math. Soc. $($N.S.$)$ 11 (1984) 386
[14] , Characteristic classes of surface bundles, Invent. Math. 90 (1987) 551
[15] , Structure of the mapping class groups of surfaces: a survey and a prospect, from: "Proceedings of the Kirbyfest (Berkeley, CA, 1998)", Geom. Topol. Monogr. 2, Geom. Topol. Publ., Coventry (1999) 349
[16] , Towards an enumerative geometry of the moduli space of curves, from: "Arithmetic and geometry, Vol II", Progr. Math. 36, Birkhäuser (1983) 271
[17] , The decorated Teichmüller space of punctured surfaces, Comm. Math. Phys. 113 (1987) 299
[18] , The Poincaré dual of the Weil–Petersson Kähler two-form, from: "Perspectives in mathematical physics", Conf. Proc. Lecture Notes Math. Phys., III, Int. Press, Cambridge, MA (1994) 229
[19] , Homotopy associativity of $H$–spaces I, II, Trans. Amer. Math. Soc. 108 $(1963)$, 275-292; ibid. 108 (1963) 293
[20] , Quadratic differentials, Ergebnisse der Mathematik und ihrer Grenzgebiete (3) 5, Springer (1984)
Cité par Sources :