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Apr 5, 2020 at 5:55 review Close votes
Apr 5, 2020 at 22:07
Apr 5, 2020 at 5:19 history edited YCor CC BY-SA 4.0
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Aug 18, 2017 at 14:10 comment added abx About your edited question: for which algebra structure???
Aug 18, 2017 at 14:04 history edited cheyne CC BY-SA 3.0
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Aug 16, 2017 at 21:36 comment added Jason Starr That theorem is due to Kato, and it is discussed in Serre's "Galois cohomology". Serre discusses the difference between fields that are of "cohomological dimension $\leq 1$" and fields that are of "dimension $\leq 1$". The second notion is a strengthening of the first notion intended to incorporate the $p$-torsion of the Brauer group. I believe Gille is writing a book about the corresponding modification of 'etale cohomology (for which "cohomological dimension $\leq 1$" is Serre's notion of "dimension $\leq 1$").
Aug 15, 2017 at 18:24 comment added Daniel Litt You may enjoy Theorem 9.2.4 in "Central Simple Algebras and Galois Cohomology" by Philippe Gille, Tamás Szamuely, which classifies $p$-Torsion Brauer classes (in characteristic $p$!) in terms of differential forms. IIRC this theorem is originally due to Kato. I don't know a related result in characteristic zero, which is what you seem to be looking for.
Aug 15, 2017 at 14:02 comment added Fang Hung-chien Side remark. In characteristic $p$>0, the pushforward of the sheaf of (crystalline) differential operators on $X$ to its Frobenius twist $X^{(p)}$, has a natural Azumaya algebra structure over the structure sheaf of the cotangent bundle of $X^{(p)}$.
Aug 15, 2017 at 13:53 answer added Ben Webster timeline score: 3
Aug 15, 2017 at 12:30 history asked cheyne CC BY-SA 3.0