{ "id": "2205.10344", "version": "v1", "published": "2022-05-20T17:56:27.000Z", "updated": "2022-05-20T17:56:27.000Z", "title": "Hecke orbits on Shimura varieties of Hodge type", "authors": [ "Marco D'Addezio", "Pol van Hoften" ], "comment": "61 pages", "categories": [ "math.AG", "math.NT" ], "abstract": "We prove the Hecke orbit conjecture of Chai--Oort for Shimura varieties of Hodge type at primes of good reduction, under a mild assumption on the size of the prime. Our proof uses a new generalisation of Serre--Tate coordinates for deformation spaces of central leaves in such Shimura varieties, constructed using work of Caraiani--Scholze and Kim. We use these coordinates to give a new interpretation of Chai--Oort's notion of strongly Tate-linear subspaces of these deformation spaces. This lets us prove upper bounds on the local monodromy of these subspaces using the Cartier--Witt stacks of Bhatt--Lurie. We also prove a rigidity result in the style of Chai--Oort for strongly Tate-linear subspaces. Another main ingredient of our proof is a new result on the local monodromy groups of $F$-isocrystals \"coming from geometry\", which should be of independent interest.", "revisions": [ { "version": "v1", "updated": "2022-05-20T17:56:27.000Z" } ], "analyses": { "subjects": [ "11G18", "14G35" ], "keywords": [ "shimura varieties", "hodge type", "strongly tate-linear subspaces", "deformation spaces", "local monodromy groups" ], "note": { "typesetting": "TeX", "pages": 61, "language": "en", "license": "arXiv", "status": "editable" } } }