diff --git a/CONTRIBUTORS b/CONTRIBUTORS index d77a630aa..fecf25ddf 100644 --- a/CONTRIBUTORS +++ b/CONTRIBUTORS @@ -119,6 +119,7 @@ Jackson Morrow Yusuf Mustopa David Mykytyn Josh Nichols-Barrer +Kien Nguyen Thomas Nyberg Masahiro Ohno Catherine O'Neil diff --git a/etale-cohomology.tex b/etale-cohomology.tex index d41b94987..f486ba620 100644 --- a/etale-cohomology.tex +++ b/etale-cohomology.tex @@ -154,10 +154,14 @@ \section{The \'etale topology} (resp.\ abelian group, vector space, etc) $\mathcal{F}(U)$, \item for each pair $U, \ U'$ of \'etale schemes over $X$, and each morphism $U \to U'$ over $X$ (which is -automatically \'etale) a restriction map $\rho^{U}_{U'} -: \mathcal{F}(U) \to \mathcal{F}(U')$ +automatically \'etale) a restriction map +$\rho^{U'}_U : \mathcal{F}(U') \to \mathcal{F}(U)$ \end{enumerate} -These data have to satisfy the following {\it sheaf axiom}: +These data have to satisfy the condition that $\rho^U_U = \text{id}$ +in case of the identity morphism $U \to U$ +and that $\rho^{U'}_U \circ \rho^{U''}_{U'} = \rho^{U''}_U$ +when we have morphisms $U \to U' \to U''$ of schemes \'etale over $X$ +as well as the following {\it sheaf axiom}: \begin{itemize} \item[$(*)$] for every \'etale covering $\{ \varphi_i : U_i \to X\}_{i \in I}$, the diagram