ScalingStacks

Definition 2.6 . [02IN]

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Definition 2.6.

A rational point of XKanX_{K}^{\text{\rm an}} is a point p∈Xanp\in X^{{\text{\rm an}}} satisfying ℋ⁡(p)=K\mathscr{H}(p)=K. We denote by Xan​(K)X^{\text{\rm an}}(K) the set of rational points of XanX^{{\text{\rm an}}}. More generally, for a complete extension K′K^{\prime} of KK, the set of K′K^{\prime}-rational points of XanX^{{\text{\rm an}}} is defined as Xan​(K′)=XK′an​(K′)X^{\text{\rm an}}(K^{\prime})=X^{\text{\rm an}}_{K^{\prime}}(K^{\prime}). There is a map Xan​(K′)→XanX^{{\text{\rm an}}}(K^{\prime})\to X^{{\text{\rm an}}}, defined by the composing the inclusion Xan​(K′)↪XK′anX^{{\text{\rm an}}}(K^{\prime})\hookrightarrow X_{K^{\prime}}^{{\text{\rm an}}} with the map XK′an→XKanX_{K^{\prime}}^{{\text{\rm an}}}\to X_{K}^{{\text{\rm an}}} as above. The set of algebraic points of XanX^{{\text{\rm an}}} is the union of Xan​(K′)X^{{\text{\rm an}}}(K^{\prime}) for all finite extensions K′K^{\prime} of KK. Its image in XanX^{{\text{\rm an}}} is denoted XalganX^{{\text{\rm an}}}_{{\text{\rm alg}}}. We have that Xalgan={p∈X|[ℋ(p):K]<∞}X^{{\text{\rm an}}}_{{\text{\rm alg}}}=\{p\in X|\,[\mathscr{H}(p):K]<\infty\}.

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