C ∗ - extensions of tori , higher Chow groups and applications to incidence equivalence relations for algebraic cycles

  • Stefan M Uller-Stach, Essén
  • Published 1995


Let X be a smooth projective variety over an algebraically closed field k. We repeat Bloch's construction of a G m-biextension (torseur) E over CH p hom (X) × CH q hom (X) for p+q = dim(X)+1. First we show that in characteristic zero E comes via pullback from the Poincaré biextension P over the corresponding product of intermediate Jacobians-as conjectured… (More)