# Seminari del Dipartimento

 GeometriaIrrational Gushel-Mukai ThreefoldsGiovanni Mongardi 25-03-2021 - 14:30modalità telematica (telematic form) We construct an explicit complex smooth Fano threefold with Picard numer 1, index 1 and degree 10 (a Gushel-Mukai threefold) and prove that it is not rational by showing that its intermediate jacobian has a faithful  $mathrm{PSL}(2,F_{11})$ action. The construction is based on a very special double EPW sextic. This is joint work with O. Debarre.  org: Barbara Bolognese