The 1.5-type and stable classification of surfaces in 4-manifolds

Speaker(s)

Simona Vesela

Affiliation

MPIM Bonn

Language of the talk

English

Date

Feb. 25, 2026, 10:30 a.m.

Room

room 4070

Seminar

Seminar Algebraic Topology

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The 1.5-type is a structure on a normal bundle of a manifold in between that of the normal 1- and 2-types of modified surgery.  In a special case it was first used by Hambleton and Kreck in 1993. In an ongoing project I introduce the general theory of 1.5-types and explain their application to external stable classification of surfaces in simply connected 4-manifolds with examples.

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