On homological notions of Banach algebras related to a character (1401.2558v2)

Abstract: In this paper, we countinue our work in \cite{11}. We show that $L^{1}(G,w)$ is $\phi_{0}$-biprojective if and only if $G$ is compact, where $\phi_{0}$ is the augmentation character. We introduce the notions of character Johnson amenability and character Johnson contractibility for Banach algebras. We show that $\ell^{1}(S)$ is pseudo-amenable if and only if $\ell^{1}(S)$ is character Johnson-amenable, provided that $S$ is a uniformly locally finite band semigroup. We give some conditions whether $\phi$-biprojectivity ($\phi$-biflatness) of $\ell^{1}(S)$ implies the finiteness (amenability) of $S$, respectively.