A surface with representable CH0-group but no universal zero-cycle

Abstract

We introduce a new obstruction to the existence of a universal 0-cycle on a smooth projective complex variety. As an application, we construct a smooth projective complex surface whose Chow group of 0-cycles is representable but which does not admit a universal 0-cycle. This provides a two-dimensional analogue of Voisin's recent threefold counterexample to a question of Colliot-Th\'el\`ene. As a further consequence, we exhibit the first example of a smooth projective threefold of Kodaira dimension zero carrying a non-torsion Hodge class of degree 4 that is not algebraic. The construction relies on the geometry of bielliptic surfaces of type 2.

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