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Difference fields and descent in algebraic dynamics, II

137   0   0.0 ( 0 )
 Added by Ehud Hrushovski
 Publication date 2008
  fields
and research's language is English




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This second part of the paper strengthens the descent theory described in the first part to rational maps, arbitrary base fields, and dynamics given by correspondences. We obtain in particular a decomposition of any difference field extension into a tower of finite, field-internal and one-based difference field extensions. This is needed in order to obtain the dynamical Northcott Theorem 1.11 of Part I in sharp form.



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