Banach Journal of Mathematical Analysis

Some homological and cohomological notions on $T$-Lau product of Banach algebras

Hossein Javanshiri and Mehdi Nemati

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Let $\mathcal A$ and $\mathcal B$ be Banach algebras and let $T:{\mathcal B}\rightarrow{\mathcal A}$ be a continuous homomorphism. Recently, we introduced a product ${\mathcal M}:={\mathcal A}\times_T{\mathcal B}$, which is a strongly splitting Banach algebra extension of $\mathcal B$ by $\mathcal A$. In the present paper, we characterize biprojectivity, approximate biprojectivity and biflatness of ${\mathcal A}\times_T{\mathcal B}$ in terms of ${\mathcal A}$ and ${\mathcal B}$. We also study some notions of amenability such as approximate amenability and pseudo-amenability of ${\mathcal A}\times_T{\mathcal B}$.

Article information

Banach J. Math. Anal., Volume 9, Number 2 (2015), 183-195.

First available in Project Euclid: 19 December 2014

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 43A07: Means on groups, semigroups, etc.; amenable groups
Secondary: 46H25: Normed modules and Banach modules, topological modules (if not placed in 13-XX or 16-XX)

Biprojectivity approximate biprojectivity biflatness approximate amenability pseudo-amenability


Nemati, Mehdi; Javanshiri, Hossein. Some homological and cohomological notions on $T$-Lau product of Banach algebras. Banach J. Math. Anal. 9 (2015), no. 2, 183--195. doi:10.15352/bjma/09-2-13.

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