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Timeline for Representations of Banach algebras

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Mar 28, 2020 at 16:33 comment added Paul Visoianu T_L (A) is not in general a C*-algebra even if A is. Am I missing something? Thanks Narutaka.
Mar 28, 2020 at 0:55 comment added Paul Visoianu Thanks Narutaka. I need these facts for more general Banach algebras. I could assume a little more: what if L is a maximal left ideal?
Mar 26, 2020 at 2:14 comment added Narutaka OZAWA In case $A$ is a C*-algebra and $L$ is a closed left ideal, $T_L(A)$ is isometrically isomorphic to the C*-algebra $A/\ker T_L$. I guess it's not that simple for general Banach algebras.
Mar 23, 2020 at 21:10 comment added Paul Visoianu The kernel is a two sided ideal, cannot equal L (a left ideal),
Mar 22, 2020 at 20:12 comment added Paul Visoianu Thanks, but I do not know when this happens in general. It may happen even if the norms are not equal.
Mar 22, 2020 at 19:58 comment added Nik Weaver Well, it would be easy to give examples. In "reasonable" cases the kernel of $T_L$ is $L$ and the norm of $T_L(a)$ equals the norm of $a + L$ in $A/L$. So $T_L(A)$ is isometric to $A$ and therefore complete. There will be degenerate examples where that isn't true, though. A good question would be: is $T_L(A)$ always closed?
Mar 22, 2020 at 18:54 comment added Paul Visoianu I am currently studying the invariant subspaces of strictly cyclic Banach algebras and their reflexivity (as operator algebras).
Mar 22, 2020 at 18:34 comment added Nik Weaver How did this question arise?
Mar 22, 2020 at 17:55 history edited YCor CC BY-SA 4.0
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Mar 22, 2020 at 17:55 review First posts
Mar 22, 2020 at 19:31
Mar 22, 2020 at 17:51 history asked Paul Visoianu CC BY-SA 4.0