Geometric methods for cohomological invariants
نویسنده
چکیده
We explain how to exploit Rost’s theory of Chow groups with coefficients to carry some computations of cohomological invariants. In particular, we use the idea of the “stratification method” introduced by Vezzosi. We recover a number of known results, with very different proofs. We obtain some new information on spin groups and on PGL4.
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تاریخ انتشار 2007