{ "id": "math/0511310", "version": "v2", "published": "2005-11-11T19:35:01.000Z", "updated": "2006-11-20T14:01:37.000Z", "title": "Stable domination and independence in algebraically closed valued fields", "authors": [ "Deirdre Haskell", "Ehud Hrushovski", "Dugald Macpherson" ], "categories": [ "math.LO", "math.AG" ], "abstract": "We seek to create tools for a model-theoretic analysis of types in algebraically closed valued fields (ACVF). We give evidence to show that a notion of 'domination by stable part' plays a key role. In Part A, we develop a general theory of stably dominated types, showing they enjoy an excellent independence theory, as well as a theory of definable types and germs of definable functions. In Part B, we show that the general theory applies to ACVF. Over a sufficiently rich base, we show that every type is stably dominated over its image in the value group. For invariant types over any base, stable domination coincides with a natural notion of `orthogonality to the value group'. We also investigate other notions of independence, and show that they all agree, and are well-behaved, for stably dominated types. One of these is used to show that every type extends to an invariant type; definable types are dense. Much of this work requires the use of imaginary elements. We also show existence of prime models over reasonable bases, possibly including imaginaries.", "revisions": [ { "version": "v2", "updated": "2006-11-20T14:01:37.000Z" } ], "analyses": { "subjects": [ "12J10", "03C45", "03C60" ], "keywords": [ "algebraically closed valued fields", "stable domination", "invariant type", "stably dominated types", "value group" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math.....11310H" } } }