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Continuous automorphisms of Cremona groups

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 نشر من قبل Susanna Zimmermann
 تاريخ النشر 2019
  مجال البحث
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We show that if a group automorphism of a Cremona group of arbitrary rank is also a homeomorphism with respect to either the Zariski or the Euclidean topology, then it is inner up to a field automorphism of the base-field. Moreover, we show that a similar result holds if we consider groups of polynomial automorphisms of affine spaces instead of Cremona groups.



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