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Equivalence relations invariant under group actions

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 نشر من قبل Tomasz Rzepecki
 تاريخ النشر 2016
  مجال البحث
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 تأليف Tomasz Rzepecki




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We extend some recent results about bounded invariant equivalence relations and invariant subgroups of definable groups: we show that type-definability and smoothness are equivalent conditions in a wider class of relations than heretofore considered, which includes all the cases for which the equivalence was proved before. As a by-product, we show some analogous results in purely topological context (without direct use of model theory).



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