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Coformality around fibrations and cofibrations

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 نشر من قبل Ruizhi Huang
 تاريخ النشر 2021
  مجال البحث
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 تأليف Ruizhi Huang




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We show that in a fibration the coformality of the base space implies the coformality of the total space under reasonable conditions, and these conditions can not be weakened. The result is partially dual to the classical work of Lupton cite{Lup} on the formality within a fibration. Our result has two applications. First, we show that for certain cofibrations, the coformality of the cofiber implies the coformality of the base. Secondly, we show that the total spaces of certain spherical fibrations are Koszul in the sense of Berglund cite{Ber}.



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