$E_2$-formality via obstruction theory
Annales Henri Lebesgue, Volume 8 (2025), pp. 699-720

Metadata

Keywords $E_2$-formality, obstruction theory, Davis–Januszkiewicz spaces

Abstract

We attack the question of $E_2$-formality of differential graded algebras over $\mathbb{F}_p$ via obstruction theory. We are able to prove that $E_2$-algebras whose cohomology ring is a polynomial algebra on even degree classes are formal. As a consequence we prove $E_2$-formality of the classifying space of some compact Lie groups or of Davis–Januszkiewicz spaces.


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