The formal schemes are typically studied over noetherian local rings, or in Grothendieck school in somewhat larger generality of pseudocompact rings. However some very useful rings do not have any pseudocompact topology. Morris and Pareigis invented an extension of the theory of formal schemes over an arbitrary ground ring which involves some neat categorical ideas.
Last revised on February 29, 2016 at 20:47:37. See the history of this page for a list of all contributions to it.