{ "id": "1407.5707", "version": "v2", "published": "2014-07-22T01:52:20.000Z", "updated": "2016-06-08T05:32:07.000Z", "title": "The Geometry of Hida Families I: $Λ$-adic de Rham cohomology", "authors": [ "Bryden Cais" ], "comment": "This article is a revised version of part of arXiv:1209.0046", "categories": [ "math.NT" ], "abstract": "We construct the $\\Lambda$-adic de Rham analogue of Hida's ordinary $\\Lambda$-adic \\'etale cohomology and of Ohta's $\\Lambda$-adic Hodge cohomology, and by exploiting the geometry of integral models of modular curves over the cyclotomic extension of $\\mathbf{Q}_p$, we give a purely geometric proof of the expected finiteness, control, and $\\Lambda$-adic duality theorems. Following Ohta, we then prove that our $\\Lambda$-adic module of differentials is canonically isomorphic to the space of ordinary $\\Lambda$-adic cuspforms. In the sequel to this paper, we construct the crystalline counterpart to Hida's ordinary $\\Lambda$-adic \\'etale cohomology, and employ integral $p$-adic Hodge theory to prove $\\Lambda$-adic comparison isomorphisms between all of these cohomologies. As applications of our work in this paper and the sequel, we will be able to provide a \"cohomological\" construction of the family of $(\\varphi,\\Gamma)$-modules attached to Hida's ordinary $\\Lambda$-adic \\'etale cohomology by the work of Dee, as well as a new and purely geometric proof of Hida's finitenes and control theorems. We are also able to prove refinements of theorems of Mazur-Wiles and of Ohta.", "revisions": [ { "version": "v1", "updated": "2014-07-22T01:52:20.000Z", "journal": null, "doi": null }, { "version": "v2", "updated": "2016-06-08T05:32:07.000Z" } ], "analyses": { "subjects": [ "11F33", "11F67", "11G18", "11R23" ], "keywords": [ "adic etale cohomology", "rham cohomology", "hida families", "hidas ordinary", "purely geometric proof" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1407.5707C" } } }