The Noether-Lefschetz conjecture and its generalizations
-- Zhiyuan Li, April 24, 2015
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According to Maulik and Pandharipande, there is a
conjectural description of the Picard group of the moduli space of
K3 surfaces of any given genus, called the Noether-Lefschetz
conjecture. In this talk, I will talk about the proof of this
conjecture and its relation to a strengthening of the Hodge
conjecture on Shimura varieties. This is joint work with
Bergeron, Millson and Moeglin.