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CATEGORIES:Isaac Newton Institute Seminar Series
SUMMARY:Counter-examples of high Clifford index to Prym-To
relli - Izadi\, E (Georgia)
DTSTART;TZID=Europe/London:20110208T113000
DTEND;TZID=Europe/London:20110208T123000
UID:TALK29767AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/29767
DESCRIPTION:For an 'etale double cover of smooth curves\, the
Prym variety is essentially the ``difference'' bet
ween the jacobians of the two curves. The Torelli
problem for the Prym map asks when two double cove
rs have the same Prym variety. It is known that th
e Prym map from the moduli space of double covers
of curves of genus g at least 7 to principally pol
arized abelian varieties of dimension g-1 is gener
ically injective. Counter-examples to the injectiv
ity of the Prym map were\, up to now\, given by Do
nagi's tetragonal construction and by Verra's cons
truction for plane sextics. It was conjectured tha
t all counter-examples are obtained from double co
vers of curves of Clifford index at most 3. I will
discuss counter-examples to this conjecture const
ructed by myself and Herbert Lange.\n
LOCATION:Seminar Room 1\, Newton Institute
CONTACT:Mustapha Amrani
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