A Short Proof of Rost Nilpotence via Refined Correspondences
نویسندگان
چکیده
I generalize the standard notion of the composition g ◦ f of correspondences f : X → Y and g : Y → Z to the case that X and Z are arbitrary varieties but Y is smooth and projective. Using this notion, I give a short self-contained proof of Rost’s “nilpotence theorem” and a generalization of one important result used by Rost in his proof of the nilpotence theorem.
منابع مشابه
Motivic construction of cohomological invariants
The norm varieties and the varieties with special correspondences play a major role in the proof of the Bloch-Kato Conjecture by M. Rost and V. Voevodsky. In the present paper we show that a variety which possesses a special correspondence is a norm variety. As an unexpected application we give a positive answer to a problem of J.-P. Serre about groups of type E8 over Q. Apart from this we incl...
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