The Rost Invariant Has Trivial Kernel for Quasi-split Groups of Low Rank
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چکیده
For G an almost simple simply connected algebraic group defined over a field F , Rost has shown that there exists a canonical map RG : H (F, G) → H(F, Q/Z(2)). This includes the Arason invariant for quadratic forms and Rost’s mod 3 invariant for Albert algebras as special cases. We show that RG has trivial kernel if G is quasi-split of type E6 or E7. A case-by-case analysis shows that it has trivial kernel whenever G is quasi-split of low rank.
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تاریخ انتشار 2000