12 Oct
2017
12 Oct
'17
9:41 a.m.
Cari, Vi ricordo il seminario di oggi pomeriggio. A presto, Bruno ---- 12-Oct-2017 - 16:00 Sala Seminari (Dip. Matematica) <http://www.dm.unipi.it/webnew/it/aula/sala-seminari-dip-matematica> On corks with low shadow-complexity <http://www.dm.unipi.it/webnew/it/seminari/corks-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.