On algebraic $\sigma $-groups
نویسندگان
چکیده
منابع مشابه
On algebraic σ-groups
We introduce the categories of algebraic σ-varieties and σ-groups over a difference field (K,σ). Under a “linearly σ-closed” assumption on (K,σ) we prove an isotriviality theorem for σ-groups. This theorem yields immediately the key lemma in a proof of the Manin-Mumford conjecture. The present paper uses crucially ideas from [10] but in a model theory free manner. The applications to Manin-Mumf...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 2006
ISSN: 0002-9947,1088-6850
DOI: 10.1090/s0002-9947-06-04312-1