Submission: 2018, Apr 6
We determine the group of reductive cohomological degree 3 invariants of all split semisimple groups of types B, C, and D. We also present a complete description of the cohomological invariants. As an application, we show that the group of degree 3 unramified cohomology of the classifying space BG is trivial for all split semisimple groups G of types B, C, and D.
2010 Mathematics Subject Classification: 12G05, 20G10, 14M17, 20G15, 14L30, 11E72, 16H05
Keywords and Phrases: cohomological invariants; Galois cohomology; torsor; reductive algebraic group; classifying space; unramified cohomology; semisimple groups
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