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The Brauer group and indecomposable $(2,1)$ -cycles

  • Bruno Kahn (a1)


We show that the torsion in the group of indecomposable $(2,1)$ -cycles on a smooth projective variety over an algebraically closed field is isomorphic to a twist of its Brauer group, away from the characteristic. In particular, this group is infinite as soon as $b_{2}-{\it\rho}>0$ . We derive a new insight into Roǐtman’s theorem on torsion $0$ -cycles over a surface.



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The Brauer group and indecomposable $(2,1)$ -cycles

  • Bruno Kahn (a1)


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