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Timeline for Socle of an operator algebra

Current License: CC BY-SA 4.0

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Feb 24, 2022 at 13:23 comment added Onur Oktay Professor Ozawa, thanks again for your kind and helpful reply.
Feb 24, 2022 at 13:11 comment added Narutaka OZAWA Triviality of the socle of $A$ does not imply the same of the C*-envelope. An example can be derived from Parrott's example.
Feb 23, 2022 at 20:03 comment added Onur Oktay Professor @NarutakaOZAWA, as opposed to the $C^{\ast}$-algebra generated by the unilateral shift $u$, its $C^{\ast}$-envelope is $C(\mathbb{R}/\mathbb{Z})$ that has trivial socle. Is it generally true that the socle of the $C^{\ast}$-envelope of an operator algebra $A$ is $\{0\}$ if $socle(A)=\{0\}$? If not, the socle of the $C^{\ast}$-envelope is (perhaps?) a boundary ideal. Which property of $A$ suffices the socle of the $C^{\ast}$-envelope to be equal to the Shilov boundary ideal? Thank you for your time in advance.
Feb 23, 2022 at 19:37 history edited Onur Oktay CC BY-SA 4.0
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Feb 23, 2022 at 14:43 comment added Onur Oktay @NarutakaOZAWA Thank you for your kind reply and for the precise reference to the section in Pisier's book. It's not so long ago that I started to learn the operator space theory from the basics, starting from the books of Blecher & le Merdy, Effros & Ruan, Pisier, Paulsen, along with next-step books to read on my Jabref shelf. Thanks for bearing with me and your kind response.
Feb 23, 2022 at 13:40 comment added Narutaka OZAWA Both are false. As to Q1, any nontrivial $A$ such that $A\cap A^*=\mathbb{C}1$ is a counterexample, by considering the conjugation by an invertible operator. It makes more sense to ask if every contractive homomorphism is completely contractive. Pisier calls such operator algebras to be "full" and presents examples and counterexamples in his book [Introduction to Operator Space Theory, Section 26]. As to Q2, the unital operator algebra $A$ generated by the unilateral shift is a counterexample.
Feb 22, 2022 at 23:48 history edited YCor
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Feb 22, 2022 at 22:27 history edited Onur Oktay CC BY-SA 4.0
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Feb 22, 2022 at 22:15 history asked Onur Oktay CC BY-SA 4.0