The tempered disk and the tempered cohomology

Abstract

Let V be a complete discretely valued ring of mixed characteristic, with fraction field K and residue field k. Using the ind-Banach framework for derived analytic geometry, we view generic fibers of V-schemes as derived analytic spaces. This approach yields a refined notion of spectrum, richer than that of classical rigid geometry: for ex- ample we may have open subsets whose structure sheaf contains functions of logarithmic growth. In this setting, the transfer theorem for the log-growth of solutions of p-adic differ- ential equations becomes a natural continuity statement, analogous to the classical transfer theorem for radii of convergence on Berkovich spaces. Motivated by ideas of Scholze, we introduce tempered tubular neighborhoods of smooth k-schemes and define a new tempered de Rham cohomology via the derived de Rham complex of these tubes. Finally, we establish a comparison theorem showing that, for smooth proper k-schemes, tempered de Rham cohomology agrees with crystalline cohomology.