dorsal/arxiv
View SchemaA note on strong similarity and the Connes embedding problem
| Authors | Gilles Pisier |
|---|---|
| Categories | |
| ArXiv ID | 2601.10654vv1 |
| URL | https://arxiv.org/abs/2601.10654 |
| License | http://creativecommons.org/licenses/by/4.0/ |
Abstract
We show that there exists a completely bounded (c.b. in short) homomorphism $u$ from a $C^*$-algebra $C$ with the lifting property (in short LP) into a QWEP von Neumann algebra $N$ that is not strongly similar to a $*$-homomorphism, i.e. the similarities that ``orthogonalize" $u$ (which exist since $u$ is c.b.) cannot belong to the von Neumann algebra $N$. Moreover, the map $u$ does not admit any c.b. lifting up into the WEP $C^*$-algebra of which $N$ is a quotient. We can take $C=C^*(G)$ (full $C^*$-algebra) where $G$ is any nonabelian free group and $N= B(H)\bar \otimes M$ where $M$ is the von Neumann algebra generated by the reduced $C^*$-algebra of $G$.
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"abstract": "We show that there exists a completely bounded (c.b. in short) homomorphism $u$ from a $C^*$-algebra $C$ with the lifting property (in short LP) into a QWEP von Neumann algebra $N$ that is not strongly similar to a $*$-homomorphism, i.e. the similarities that ``orthogonalize\" $u$ (which exist since $u$ is c.b.) cannot belong to the von Neumann algebra $N$. Moreover, the map $u$ does not admit any c.b. lifting up into the WEP $C^*$-algebra of which $N$ is a quotient. We can take $C=C^*(G)$ (full $C^*$-algebra) where $G$ is any nonabelian free group and $N= B(H)\\bar \\otimes M$ where $M$ is the von Neumann algebra generated by the reduced $C^*$-algebra of $G$.",
"arxiv_id": "2601.10654",
"authors": [
"Gilles Pisier"
],
"categories": [
"math.OA"
],
"license": "http://creativecommons.org/licenses/by/4.0/",
"title": "A note on strong similarity and the Connes embedding problem",
"url": "https://arxiv.org/abs/2601.10654",
"version": "v1"
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