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Ken.Wong
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This post is actually a refined question of here.

Let $N$ be an abelian von-Neumann algebra. Define densely defined derivation to be derivation $\delta:D(\delta)\rightarrow N$ where the domain is dense subalgebra in norm topology. Does $N$ admit any closed densely defined derivations? I am most interested in $l^{\infty}(\mathbb{N})$ and $L^{\infty}[0,1]$. My gut feeling is that it doesn't since their real rank is zero, but I don't know how to show that.

This post is actually a refined question of here.

Let $N$ be an abelian von-Neumann algebra. Define densely defined derivation to be derivation $\delta:D(\delta)\rightarrow N$ where the domain is dense subalgebra in norm topology. Does $N$ admit any densely defined derivations? I am most interested in $l^{\infty}(\mathbb{N})$ and $L^{\infty}[0,1]$. My gut feeling is that it doesn't since their real rank is zero, but I don't know how to show that.

This post is actually a refined question of here.

Let $N$ be an abelian von-Neumann algebra. Define densely defined derivation to be derivation $\delta:D(\delta)\rightarrow N$ where the domain is dense subalgebra in norm topology. Does $N$ admit any closed densely defined derivations? I am most interested in $l^{\infty}(\mathbb{N})$ and $L^{\infty}[0,1]$. My gut feeling is that it doesn't since their real rank is zero, but I don't know how to show that.

improved formatting
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Ken.Wong
  • 523
  • 2
  • 7

This post is actually a refined question of here. 

Let $N$ be an abelian von-Neumann algebra. Define densely defined derivation to be derivation $\delta:D(\delta)\rightarrow N$ where the domain is dense subalgebra in norm topology. Does $N$ admit any densely defined derivations? I am most interested in $l^{\infty}(\mathbb{N})$ and $L^{\infty}[0,1]$. My gut feeling is that it doesn't since their real rank is zero, but I don't know how to show that.

This post is actually a refined question of here. Let $N$ be an abelian von-Neumann algebra. Define densely defined derivation to be derivation $\delta:D(\delta)\rightarrow N$ where the domain is dense subalgebra in norm topology. Does $N$ admit any densely defined derivations? I am most interested in $l^{\infty}(\mathbb{N})$ and $L^{\infty}[0,1]$. My gut feeling is that it doesn't since their real rank is zero, but I don't know how to show that.

This post is actually a refined question of here. 

Let $N$ be an abelian von-Neumann algebra. Define densely defined derivation to be derivation $\delta:D(\delta)\rightarrow N$ where the domain is dense subalgebra in norm topology. Does $N$ admit any densely defined derivations? I am most interested in $l^{\infty}(\mathbb{N})$ and $L^{\infty}[0,1]$. My gut feeling is that it doesn't since their real rank is zero, but I don't know how to show that.

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Ken.Wong
  • 523
  • 2
  • 7

Densely defined derivations in von Neumann algebra(in norm topology)

This post is actually a refined question of here. Let $N$ be an abelian von-Neumann algebra. Define densely defined derivation to be derivation $\delta:D(\delta)\rightarrow N$ where the domain is dense subalgebra in norm topology. Does $N$ admit any densely defined derivations? I am most interested in $l^{\infty}(\mathbb{N})$ and $L^{\infty}[0,1]$. My gut feeling is that it doesn't since their real rank is zero, but I don't know how to show that.