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In this article, we give a first prototype-definition of overtwistedness in higher
dimensions. According to this definition, a contact manifold is called overtwisted if it
contains a plastikstufe, a submanifold foliated by the contact structure in a certain
way. In three dimensions the definition of the plastikstufe is identical to the one of
the overtwisted disk. The main justification for this definition lies in the fact that the
existence of a plastikstufe implies that the contact manifold does not have a
(semipositive) symplectic filling.
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