Demonstratio Mathematica (Jun 2025)
ωℒ{\omega }_{{\mathcal{ {\mathcal L} }}}-biprojective and ω¯\overline{\omega }-contractible Banach algebras
Abstract
For a given Banach algebra ℳ{\mathcal{ {\mathcal M} }} and a continuous endomorphism ω\omega on ℳ{\mathcal{ {\mathcal M} }}, we define ℳ{\mathcal{ {\mathcal M} }} to be ωℒ{\omega }_{{\mathcal{ {\mathcal L} }}}-biprojective and ω¯\overline{\omega }-contractible. We then explore the relationship between them. Additionally, we show that l1(N∨){l}^{1}\left({{\mathbb{N}}}_{\vee }) is a ωℒ{\omega }_{{\mathcal{ {\mathcal L} }}}-biprojective Banach algebra. Finally, we examine the concept of ω\omega -pseudo amenability and ω\omega -approximate biprojectivity in Banach algebras. We demonstrate that for every unital Banach algebra ℳ{\mathcal{ {\mathcal M} }}, ω\omega -approximate biprojectivity and ω\omega -pseudo contractibility coincide.
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