✦ LIBER ✦

Characterization of minimal Pfister neighbors via Rost projectors

✍ Scribed by Nikita A. Karpenko

Publisher: Elsevier Science
Year: 2001
Tongue: English
Weight: 250 KB
Volume: 160
Category: Article
ISSN: 0022-4049
DOI: 10.1016/s0022-4049(00)00064-5

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✦ Synopsis

Let be an anisotropic nine-dimensional quadratic form over a ÿeld (of characteristic = 2). We show that the projective quadric given by possesses a Rost projector if and only if is a Pÿster neighbor. The following consequence of this result gives the initial step in the construction [10] of the ÿeld with the u-invariant 9: if is not a Pÿster neighbor and the Schur index of its even Cli ord algebra is at least 4, then stays anisotropic over the function ÿeld of any 9-dimensional form nonsimilar to .