Uniform Bounds and Ultraproducts of Cycles
نویسندگان
چکیده
This paper is about the question whether a cycle in the l-adic cohomology of a smooth projective variety over Q, which is algebraic over almost all finite fields Fp, is also algebraic over Q. We use ultraproducts respectively nonstandard techniques in the sense of A. Robinson, which the authors applied systematically to algebraic geometry in [BS07] and [BS08]. We give a reformulation of the question in form of uniform bounds for the complexity of algebraic cycles over finite fields.
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