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I am looking for a general survey on the finite generation properties of

$$H^i(F,\mathbb{Z}_p(j))$$

for fields $F$. Here I refer to Galois cohomology (continuous group cohomology) and the group is defined as the inverse limit over $H^i(F,\mathbb{Z}/p^n(j))$. The only criterion I have seen (and which is already in the work of Tate) is that if $H^i(F,\mathbb{Z}/p^n(j))$ is finite for all $n$, then the above group is a finitely generated $\mathbb{Z}_p$-module.

For example, for finite or local fields this is true, but for number fields it fails (as can, for example, be seen from the Poitou–Tate exact sequence). However, I struggle to find references to discuss other types of fields:

  1. From the above, I expect that finite generation should be expected to fail for all fields which are finitely generated over the rationals,
  2. I would expect similarly no finite generation for finitely generated field of transcendence degree at least one over a finite field (using CFT for curves?)
  3. perhaps finite generation holds for all $d$-local fields, e.g. $\mathbb{Q}_p((t_1))\ldots((t_r))$ for any r?
  4. and maybe(?) finite generation fails for function fields of varieties of dimension at least one over local fields?
  5. what about a function field of a curve over an algebraically closed field?
  6. perhaps something like finite generation could hold over fields like the maximal cyclotomic extension of the rationals (the maximal abelian extension) or maximal extensions ramified only over a single prime?

Most of these are speculations. Does anyone have a good reference to get a good overview? I would similarly like to know about cofiniteness properties of $H^i(F,\mathbb Q_p/\mathbb Z_p(j))$, which I would expect to sometimes just be dual to the above question in the presence of some form of CFT?

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    $\begingroup$ @LSpice In this context, that notation refers to a Tate twist. Usually square brackets would be used to adjoin an element to a ring, and round brackets used for fields, assuming we want it to stay a field after adjoining, but $\mathbb Z_p$ is not a field. $\endgroup$
    – Will Sawin
    Commented Oct 19, 2022 at 15:03

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