ScalingStacks

[0MJ7]

Lemma 8.6. The Yoneda embedding Ξ₯n→𝒫⁑(Ξ₯n)\Upsilon_{n}\to\pre(\Upsilon_{n}) factors through a fully-faithful inclusion

Ξ₯nβ†ͺτ≀0​𝒫⁑(Ξ₯n).\Upsilon_{n}\hookrightarrow\tau_{\leq 0}\pre(\Upsilon_{n}).

This induces a fully-faithful nerve functor

g:Gauntnβ†ͺτ≀0​Sβˆ’1​𝒫⁑(Ξ₯n).g:\gaunt_{n}\hookrightarrow\tau_{\leq 0}S^{-1}\pre(\Upsilon_{n}).
[0MJ8]

Proof. The 0-truncated objects of 𝒫⁑(Ξ₯n)\pre(\Upsilon_{n}) are precisely those presheaves of spaces taking values in the 0-truncated spaces, i.e., functors Ξ₯nopβ†’Set\Upsilon_{n}^{\mathrm{op}}\to\set. The 0-truncated objects of Cat(∞,n)=Sβˆ’1​𝒫⁑(Ξ₯n)\cat_{(\infty,n)}=S^{-1}\pre(\Upsilon_{n}) consist of precisely those 0-truncated objects of 𝒫⁑(Ξ₯n)\pre(\Upsilon_{n}) which are SS-local. By Lemma 6.6, the nerve of every gaunt nn-category is SS-local, and so the result follows. ∎

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

Clark Barwick, Christopher Schommer-Pries

Original source: arXiv:1112.0040v6

Original source Β· 1112.0040v6