\(\varphi \)-biprojectivity of Banach algebras with applications to hypergroup algebras (Q2414177)

In this paper, the authors study the notions of $\varphi$-biprojectivity and $\varphi$-Johnson contractibility of certain Banach algebras. In fact, they characterize $\varphi$-biprojectivity of hypergroup algebras. They show that the hypergroup algebra $L^{1}(K)$ is $\varphi$-biprojective if and only if $K$ is compact. Some results about the Segal algebras related to the hypergroup algebras are given.