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Reductive group torsors on a complement of a smooth divisor

AbstractA conjecture of Nisnevich predicts that for a smooth variety X over a field, a smooth divisor D in X, and a totally isotropic reductive X-group scheme G, every generically trivial G-torsor on X \ D trivializes Zariski locally on X. I will discuss this conjecture and related questions about torsors under reductive groups over regular rings.

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Ref: K.Cesnavivius, The Bass-Quillen phenomenon for reductive group torsors