2 3 O ct 1 99 8 PERIODIC CYCLIC HOMOLOGY AS SHEAF COHOMOLOGY
نویسنده
چکیده
0. Introduction. This paper continues the study of the noncommutative infinitesimal cohomology we introduced in [3]. This is the cohomology of sheaves on a noncommutative version of the commutative infinitesimal site of Grothendieck ([8]). Grothendieck showed that, for a smooth scheme X of characteristic zero, the cohomology of the structure sheaf on the infinitesimal site gives de Rham cohomology:
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