ScalingStacks

0PD3

Remark 8.2.6. Consider ξ¯1+:𝐑>0→Zopp,x↦ξ2−​(−x)\bar{\xi}_{1}^{+}:{\mathbf{R}}_{>0}\to Z^{{\operatorname{opp}\nolimits}},\ x\mapsto\xi_{2}^{-}(-x) and ξ¯2−:𝐑<0→Zopp,x↦ξ1+​(−x)\bar{\xi}_{2}^{-}:{\mathbf{R}}_{<0}\to Z^{{\operatorname{opp}\nolimits}},\ x\mapsto\xi_{1}^{+}(-x). There is an isomorphism (Zopp)ξ¯→∼(Zξ)opp(Z^{\operatorname{opp}\nolimits})_{\bar{\xi}}\mathrel{\mathop{\kern 0.0pt\to}\limits^{\sim}}(Z_{\xi})^{\operatorname{opp}\nolimits} that is the identity on ZZ and x↦−xx\mapsto-x on 𝐑{\mathbf{R}}. This provides an isomorphism (𝒮∙​(Zξ))opp→∼𝒮∙​(Zξ¯opp)({\mathcal{S}}^{\bullet}(Z_{\xi}))^{\operatorname{opp}\nolimits}\mathrel{\mathop{\kern 0.0pt\to}\limits^{\sim}}{\mathcal{S}}^{\bullet}(Z^{{\operatorname{opp}\nolimits}}_{\bar{\xi}}). It induces isomorphisms

Hom𝒮∙​(Z)⁡(S⊔(−n,−1),T⊔(1,n))→∼Hom𝒮∙​(Zopp)⁡(T⊔(−n,−1),S⊔(1,n)).\operatorname{Hom}\nolimits_{{\mathcal{S}}^{\bullet}(Z)}(S\sqcup(-n,-1),T\sqcup(1,n))\mathrel{\mathop{\kern 0.0pt\to}\limits^{\sim}}\operatorname{Hom}\nolimits_{{\mathcal{S}}^{\bullet}(Z^{\operatorname{opp}\nolimits})}(T\sqcup(-n,-1),S\sqcup(1,n)).

This restricts to isomorphisms between AnA_{n} (resp. BnB_{n}, DnD_{n}, EnE_{n}, FnF_{n}) for ZZ and AnA_{n} (resp. BnB_{n}, DnD_{n}, FnF_{n}, EnE_{n}) for ZoppZ^{\operatorname{opp}\nolimits}.

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

Andrew Manion, Raphael Rouquier

Original source: arXiv:2009.09627v2