Dimensions, matroids, and dense pairs of first-order structures
نویسندگان
چکیده
منابع مشابه
Dimensions, matroids, and dense pairs of first-order structures
A structure M is pregeometric if the algebraic closure is a pregeometry in all M ′ elementarily equivalent to M . We define a generalisation: structures with an existential matroid. The main examples are superstable groups of U-rank a power of ω and d-minimal expansion of fields. Ultraproducts of pregeometric structures expanding a field, while not pregeometric in general, do have an unique exi...
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A structure M is pregeometric if the algebraic closure is a pregeometry in all M ′ elementarily equivalent to M . We define a generalisation: structures with an existential matroid. The main examples are superstable groups of U-rank a power of ω and d-minimal expansion of fields. Ultraproducts of pregeometric structures expanding a field, while not pregeometric in general, do have an unique exi...
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ژورنال
عنوان ژورنال: Annals of Pure and Applied Logic
سال: 2011
ISSN: 0168-0072
DOI: 10.1016/j.apal.2011.01.003