Generic fibrations around multiple fibers
نویسندگان
چکیده
Given some type of fibration on a 4-manifold X with a torus regular fiber T , we may produce a new 4-manifold XT by performing torus surgery on T . There is a natural way to extend the fibration to XT , but a multiple fiber (nongeneric) singularity is introduced. We construct explicit generic fibrations (with only indefinite fold singularities) in a neighborhood of this multiple fiber. As an application this gives explicit constructions of broken Lefschetz fibrations on all elliptic surfaces (e.g., the family E(n)p,q). As part of the construction we produce generic fibrations around exceptional fibers of Seifert fibered spaces.
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