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arXiv · 1307.2143

More Examples of Non-Rational Adjoint Groups

Nivedita Bhaskhar
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Abstract

We give a recursive construction to produce examples of quadratic forms q_n in the n-th power of the fundamental ideal in the Witt ring whose corresponding adjoint groups PSO(q_n) are not stably rational. Computations of the R-equivalence classes of adjoint classical groups by A.S. Merkurjev are used to show that these groups are not R-trivial. This extends earlier results of A.S. Merkurjev and P.Gille where the forms considered have non-trivial and trivial discriminants respectively.

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Nivedita Bhaskhar. 2013-07-08. More Examples of Non-Rational Adjoint Groups. https://arxiv.org/abs/1307.2143

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