Definition 64.14.2. With \Lambda , X, k, K as in Definition 64.14.1. Since K\in D_{ctf}(X, \Lambda ), for any geometric point \bar x of X, the complex K_{\bar x} is a perfect complex (in D_{perf}(\Lambda )). As we have seen in Section 64.3, the Frobenius \pi _ X acts on K_{\bar x}. The local Lefschetz number of K is the sum
\sum \nolimits _{x\in X(k)} \text{Tr}(\pi _ x |_{K_{\overline{x}}})
which is again an element of \Lambda ^\natural .
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Comment #8300 by Xiaolong Liu on
Comment #8926 by Stacks project on