## J.-L. Colliot-Thélène: A rationality question for the adjoint group

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Summary :
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Let G be a simple algebraic group over the complex field, let g be
its Lie algebra.
We investigate the question whether the field of rational functions
of g is purely transcendental
over the subfield of invariant rational functions for the adjoint
representation of G on g.
This is joint work with B. Kunyavskii, V. L. Popov and Z. Reichstein.