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In several expositions of $\infty$-categories, I read that singular cohomology of a topological space with integral coefficients is a sheaf valued in $D(\mathbb{Z})$, if we consider Top and $D(\mathbb{Z})$ as $\infty$-categories. This has the advantage of getting easier proofs of known results and even improve them. For instance, I heard one can prove that singular cohomology and sheaf cohomology agree not just for locally contractible spaces, but for all locally weakly contractible spaces. However, I cannot find an exposition of why this is true or examples of working with it, it is only mentioned, like in these wonderful notes by Adeel Khan https://www.preschema.com/lecture-notes/2023-kias/dagkias.pdf.

Is there a reference detailing why singular cohomology of a space is a sheaf of $\infty$-categories? Ideally also working with it, for example proving that it agrees with sheaf cohomology for locally weakly contractible spaces?

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    $\begingroup$ I think Petersen, A remark on singular and sheaf cohomology may partially answer your question (but I'm not sure it's exactly what you're asking). $\endgroup$ Commented Sep 8 at 16:31
  • $\begingroup$ @R.vanDobbendeBruyn sorry for taking so long for answering, but thank you very much! It is indeed a bit helpful, although does not go so deep into the infinity business. Probably I was too lazy and should just write down stuff! $\endgroup$ Commented Sep 11 at 21:59
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    $\begingroup$ The fact that singular cohomology is a hypersheaf follows right away from the results Theorem 1.3 of this paper:D. Dugger and D. Isaksen, Topological hypercovers and A1-realizations, Math. Z. 246 (2004), no. 4, 667-689. The agreement with sheaf cohomology for locally weakly contractible spaces is a consequence; see this answer. mathoverflow.net/a/67127/1017 $\endgroup$ Commented Nov 29 at 9:16

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