Rigid Cohomology and De Rham-witt Complexes
نویسندگان
چکیده
Let k be a perfect field of characteristic p > 0, Wn = Wn(k). For separated k-schemes of finite type, we explain how rigid cohomology with compact supports can be computed as the cohomology of certain de Rham-Witt complexes with coefficients. This result generalizes the classical comparison theorem of Bloch-Illusie for proper and smooth schemes. In the proof, the key step is an extension of the Bloch-Illusie theorem to the case of cohomologies relative to Wn with coefficients in a crystal that is only supposed to be flat over Wn. Dedicated to Francesco Baldassarri, on his sixtieth birthday
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