Cari,

Vi ricordo il seminario di oggi pomeriggio.
 A presto,
   Bruno

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12-Oct-2017 16:00
On corks with low shadow-complexity
Hironobu Naoe (Tohoku University, Japan)

A cork is a contractible Stein domain that gives arise to exotic pairs of 4-manifolds. The first example was found by Akbulut. It is known that any two exotic, simply-connected, closed 4-manifolds are related by a cork twist. We show that there are no corks having shadow-complexity zero. We also show that there are infinitely many corks having shadow-conplexity 1 and 2.