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De Morgans law and the theory of fields

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 نشر من قبل Peter Johnstone
 تاريخ النشر 2008
  مجال البحث
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We show that the classifying topos for the theory of fields does not satisfy De Morgans law, and we identify its largest dense De Morgan subtopos as the classifying topos for the theory of fields of nonzero characteristic which are algebraic over their prime fields.



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