A Short Introduction to Shadows of 4-manifolds
نویسنده
چکیده
We give a self-contained introduction to the theory of shadows as a tool to study smooth 3 and 4-manifolds. The goal of the present paper twofold: on one side it is intended to be a shortcut to a basic use of the theory of shadows, on the other side it gives a sketchy overview of some of the most recent results on shadows. No original result is proved here and most of the details of the proofs are not included.
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