Let Σg → E → Σh be a surface bundle over a surface with monodromy representation ρ: π1Σh → Mod(Σg) contained in the Torelli group ℐg. We express the cup product structure in H∗(E, ℤ) in terms of the Johnson homomorphism τ: ℐg →∧ 3(H1(Σg, ℤ))∕H1(Σg, ℤ). This is applied to the question of obtaining an upper bound on the maximal n such that p1: E → Σh1,…,pn: E → Σhn are fibering maps realizing E as the total space of a surface bundle over a surface in n distinct ways. We prove that any nontrivial surface bundle over a surface with monodromy contained in the Johnson kernel Kg fibers in a unique way.
Keywords: surface bundles over surfaces, Johnson homomorphism, cup products
Salter, Nick  1
@article{10_2140_agt_2015_15_3613,
author = {Salter, Nick},
title = {Cup products, the {Johnson} homomorphism and surface bundles over surfaces with multiple fiberings},
journal = {Algebraic and Geometric Topology},
pages = {3613--3652},
year = {2015},
volume = {15},
number = {6},
doi = {10.2140/agt.2015.15.3613},
url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2015.15.3613/}
}
TY - JOUR AU - Salter, Nick TI - Cup products, the Johnson homomorphism and surface bundles over surfaces with multiple fiberings JO - Algebraic and Geometric Topology PY - 2015 SP - 3613 EP - 3652 VL - 15 IS - 6 UR - http://geodesic.mathdoc.fr/articles/10.2140/agt.2015.15.3613/ DO - 10.2140/agt.2015.15.3613 ID - 10_2140_agt_2015_15_3613 ER -
%0 Journal Article %A Salter, Nick %T Cup products, the Johnson homomorphism and surface bundles over surfaces with multiple fiberings %J Algebraic and Geometric Topology %D 2015 %P 3613-3652 %V 15 %N 6 %U http://geodesic.mathdoc.fr/articles/10.2140/agt.2015.15.3613/ %R 10.2140/agt.2015.15.3613 %F 10_2140_agt_2015_15_3613
Salter, Nick. Cup products, the Johnson homomorphism and surface bundles over surfaces with multiple fiberings. Algebraic and Geometric Topology, Tome 15 (2015) no. 6, pp. 3613-3652. doi: 10.2140/agt.2015.15.3613
[1] , The signature of fibre-bundles, from: "Global analysis (papers in honor of K Kodaira)" (editors D C Spencer, S Iyanaga), Univ. Tokyo Press (1969) 73
[2] , , , On four-manifolds fibering over surfaces, Tsukuba J. Math. 22 (1998) 333
[3] , , A primer on mapping class groups, Princeton Mathematical Series 49, Princeton Univ. Press (2012)
[4] , , Differential topology, Prentice-Hall (1974)
[5] , On surface subgroups of mapping class groups, talk at the workshop “Hot topics : Surface subgroups and cube complexes” (2013)
[6] , Algebraic topology, Cambridge Univ. Press (2002)
[7] , Four-manifolds, geometries and knots, Geometry Topology Monographs 5 (2002)
[8] , A rigidity theorem for group extensions, Arch. Math. $($Basel$)$ 73 (1999) 81
[9] , A certain type of irregular algebraic surfaces, J. Analyse Math. 19 (1967) 207
[10] , Characteristic classes of surface bundles, Invent. Math. 90 (1987) 551
[11] , Geometry of characteristic classes, Translations of Mathematical Monographs 199, Amer. Math. Soc. (2001)
[12] , Rigidity of fibering, preprint (2011)
[13] , Statistics of $3$–manifolds occsionally fibering over the circle, preprint (2014)
[14] , Surface bundles over surfaces with arbitrarily many fiberings, Geom. Topol. 19 (2015) 2901
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