Skip to main content
6 events
when toggle format what by license comment
Apr 16, 2014 at 7:54 answer added gyr timeline score: 1
Jan 23, 2013 at 9:49 comment added anon In the case of abelian varieties with good reduction (or even p-divisible groups), Faltings give a direct proof (avoiding the machinery of almost etale extensions, close in spirit to Fontaine's proof) in his "Integral crystalline cohomology over very ramified rings" paper.
Jan 23, 2013 at 8:51 comment added ACL Correction : "For abelian varieties with good reduction, an extension..."
Jan 23, 2013 at 8:51 comment added ACL An extension to more general base rings than an $p$-adic field is shown in a paper by Jean-Pierre Wintenberger, ams.org/mathscinet-getitem?mr=1293978, to be found in the volume 223 of Astérisque, ``Périodes $p$-adiques'' (edited by Fontaine). I would bet than one can obtain the more general result along the same lines (at least if the ab. var. has semi-stable reduction over $K$) by adding as an input results of Raynaud in the same volume, or uses the universal vector extension of (the connected component of) a Néron model (Mazur-Messing).
Jan 23, 2013 at 8:28 comment added user28172 What you attribute to Faltings is stated incorrectly: you need to either weaken the "crystalline" condition or assume stronger "good reduction" hypotheses on $X$. (Likewise, Fontaine's result was not for "general" abelian varieties, but rather those with good reduction, studied via their $p$-divisible groups over the valuation ring.)
Jan 23, 2013 at 4:00 history asked Tony CC BY-SA 3.0