The Ramanujan conjecture

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Proposition 3.6.   \(F\) is the inverse of the Frobenious from the action of \(\Gal(\overline{\FF}_p/\FF_p)\) on

\[\widetilde{H}^1(M_n \otimes \overline{\FF}_p, \Sym^k(R^1 f_{n*} \underline{\ZZ}_{\ell})).\]

Over \(\FF_p\), we have \(T_p = F + I_p^* V\) and \(FV = VF = p^{k+1}\).