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Stein domains and branched shadows of 4-manifolds

Francesco Costantino
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Abstract

We provide sufficient conditions assuring that a suitably decorated 2-polyhedron can be thickened to a compact 4-dimensional Stein domain. We also study a class of flat polyhedra in 4-manifolds and find conditions assuring that they admit Stein, compact neighborhoods. We base our calculations on Turaev's shadows suitably "smoothed"; the conditions we find are purely algebraic and combinatorial. Applying our results, we provide examples of hyperbolic 3-manifolds admitting "many" positive and negative Stein fillable contact structures, and prove a 4-dimensional analogue of Oertel's result on incompressibility of surfaces carried by branched polyhedra.

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Francesco Costantino. 2007-01-15. Stein domains and branched shadows of 4-manifolds. https://arxiv.org/abs/math/0504387

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