ScalingStacks

0NK6

Lemma 4.1. Let π’œ{\mathcal{A}} and ℬ{\mathcal{B}} be small spectral categories, and let f:π’œβ†’β„¬f\colon{\mathcal{A}}\mathchoice{\longrightarrow}{\rightarrow}{\rightarrow}{\rightarrow}{\mathcal{B}} be a DK-equivalence. Then the induced maps ψtri​(f)\psi_{\tri}(f) and ψperf​(f)\psi_{\perf}(f) are categorical equivalences of simplicial sets.

0NK7

Proof. If f:π’œβ†’β„¬f\colon{\mathcal{A}}\mathchoice{\longrightarrow}{\rightarrow}{\rightarrow}{\rightarrow}{\mathcal{B}} is a DK-equivalence, then one can check that (f!,fβˆ—)(f_{!},f^{*}) gives a Quillen equivalence between the spectral model categories π’œ^\widehat{{\mathcal{A}}} of π’œ{\mathcal{A}}-modules and the spectral model category ℬ^\widehat{{\mathcal{B}}} of ℬ{\mathcal{B}}-modules. Passing to underlying simplicial categories of cofibrant and fibrant objects, we see that Ξ©βˆžβ€‹(π’œ^)cf=Mod⁑(π’œ)cf\Omega^{\infty}(\widehat{{\mathcal{A}}})^{\cf}=\Mod({\mathcal{A}})^{\cf} and Ξ©βˆžβ€‹(ℬ^)=Mod⁑(ℬ)cf\Omega^{\infty}(\widehat{{\mathcal{B}}})=\Mod({\mathcal{B}})^{\cf} are DK-equivalent simplicial categories. Finally, applying the simplicial nerve yields categorically equivalent simplicial sets. Restricting to various full subcategories yields the result for ψtri​(f)\psi_{\tri}(f) and ψperf​(f)\psi_{\perf}(f). ∎

Original mathematics by the credited authors. Source collection and HTML conversion remain in progress.

Andrew J. Blumberg, David Gepner, Goncalo Tabuada

Original source: arXiv:1001.2282v4