Remark 98.20.2 (Strong effectiveness). Let S be a locally Noetherian scheme. Let \mathcal{X} be a category fibred in groupoids over (\mathit{Sch}/S)_{fppf}. Assume we have
an affine open \mathop{\mathrm{Spec}}(\Lambda ) \subset S,
an inverse system (R_ n) of \Lambda -algebras with surjective transition maps whose kernels are locally nilpotent,
a system (\xi _ n) of objects of \mathcal{X} lying over the system (\mathop{\mathrm{Spec}}(R_ n)).
In this situation, set R = \mathop{\mathrm{lim}}\nolimits R_ n. We say that (\xi _ n) is effective if there exists an object \xi of \mathcal{X} over \mathop{\mathrm{Spec}}(R) whose restriction to \mathop{\mathrm{Spec}}(R_ n) gives the system (\xi _ n).
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