ScalingStacks

[05XE]

Proof. By 2.2.9 we have a pullback square of pointed unital ∞\infty-operads

End𝒞red⁡(X)\textstyle{\operatorname{End}_{\mathcal{C}}^{\operatorname{\scriptsize{red}}}\left(X\right)\ignorespaces\ignorespaces\ignorespaces\ignorespaces\ignorespaces\ignorespaces\ignorespaces\ignorespaces}𝒞\textstyle{\mathcal{C}\ignorespaces\ignorespaces\ignorespaces\ignorespaces}𝔼∞\textstyle{\mathbb{E}_{\infty}\ignorespaces\ignorespaces\ignorespaces\ignorespaces}𝒞¯⊔,\textstyle{\underline{\mathcal{C}}_{\sqcup},}

which, by 2.2.11, induces a pullback square of multi-mapping spaces

End𝒞red⁡(X)​(m)\textstyle{\operatorname{End}_{\mathcal{C}}^{\operatorname{\scriptsize{red}}}\left(X\right)\left(m\right)\ignorespaces\ignorespaces\ignorespaces\ignorespaces\ignorespaces\ignorespaces\ignorespaces\ignorespaces}Mul𝒞⁡(X(m),X)\textstyle{\operatorname{Mul}_{\mathcal{C}}\left(X^{\left(m\right)},X\right)\ignorespaces\ignorespaces\ignorespaces\ignorespaces}𝔼∞​(m)\textstyle{\mathbb{E}_{\infty}\left(m\right)\ignorespaces\ignorespaces\ignorespaces\ignorespaces}Mul𝒞¯⊔⁡(X(m),X).\textstyle{\operatorname{Mul}_{\underline{\mathcal{C}}_{\sqcup}}\left(X^{\left(m\right)},X\right).}

The bottom map is the map Δ0→Map𝒞⁡(X⊔m,X)\Delta^{0}\to\operatorname{Map}_{\mathcal{C}}\left(X^{\sqcup m},X\right) that chooses the fold map since it is induced from the map 𝔼∞=(Δ0)⊔→𝒞¯⊔\mathbb{E}_{\infty}=\left(\Delta^{0}\right)_{\sqcup}\to\underline{\mathcal{C}}_{\sqcup}. The right vertical map is induced by pre-composition with the map σ:X⊔m→X⊗m\sigma\colon X^{\sqcup m}\to X^{\otimes m}, since it is induced by the adjunction

(−)⊔:𝐂𝐚𝐭∞⇆𝐎𝐩∞un:(−)¯.\left(-\right)_{\sqcup}\colon\mathbf{Cat}_{\infty}\leftrightarrows\mathbf{Op}_{\infty}^{\operatorname{\scriptsize{un}}}\colon\underline{\left(-\right)}.

∎

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

Tomer Schlank, Lior Yanovski

Original source: arXiv:1808.06006v3

    Original source page 14

    Original source · 1808.06006v3