If we have a compact Hausdorff space $S$, then my understanding is that the appropriate notion of the derived category of sheaves of condensed abelian groups is to consider the derived category $D_{\text{cond}}(S;\mathbb{Z})$ of sheaves of abelian groups on $*_{\text{proet}}/S$ (with the appropriate choice of the pro-etale site: compact Hausdorff spaces with finite jointly surjective covers). In this case, condensed cohomology of $S$ (which agrees with sheaf cohomology for discrete constant coefficients) is obtained using the usual formalism. Now, if $S$ is no-longer compact, but a compactly generated topological space, then there is a condensed set $\underline{S}$ associated to it. Is there a site such that sheaves of abelian groups on it gives an appropriate notion of $D_{\text{cond}}(\underline{S},\mathbb{Z})$? For example, should one take covers to be given by compactly generated spaces that pullback under any compact Hausdorff subspace of $S$ to a covering by compact Hausdorff spaces finitely many of which are jointly surjective? One property I want it to have is that "condensed cohomology" $H^i_{\text{cond}}(\underline{S};A)$ for a condensed abelian group $A$ should be the one computed on this site. Basically, I want to know if there is a nice "condensed" site for topological spaces that are not necessarily compact.
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1$\begingroup$ A condensed set gives rise to a sheaf on the pro-étale site associated to a point, and take the slice topos over it. This would recover the condensed cohomology for formal reasons. $\endgroup$– Z. MCommented Feb 22, 2022 at 11:19
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1$\begingroup$ What you (and Z.M.) write is correct. Taking the slice of the site of compact Hausdorff spaces over $\underline{S}$ gives you compact Hausdorff spaces with a map to $S$, with the usual pro-etale topology. You can also consider compactly generated spaces over $S$, as you propose. (There are many choices for the site, but the topos should be the slice topos of condensed sets over $\underline{S}$. So basically you can pick any generating class of condensed sets over $\underline{S}$, and endow it with the induced topology, to get a site that works.) $\endgroup$– Peter ScholzeCommented Feb 22, 2022 at 11:29
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