All Questions
6 questions
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Algebraic language of fundamental results in operator algebras
Ignoring topological structures of von Neumann algebras, the larger category of Baer $*$-rings was emerged. In the unique text written by Sterling K. Berberian (1), some concepts and results in von ...
1
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2
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126
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Upper triangular $2\times2$-matrices over a Baer *-ring
Let $A$ be a Baer $*$-ring. Let us denote $B$ by the space of all upper triangular matrices
$\left(\begin{array}{cc}
a_1& a_2 \\
0 & a_4
\end{array}\right)$ where $a_i$'s are in $A$. Is $B$ ...
1
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0
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112
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shifts in Baer*-rings
Let $A$ be a Baer*-ring with the unit $1$. An important point that holds in every Baer*-ring is this: for every element $y\in A$ there is an smallest projection $e_y\in A$, called the left projection ...
1
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1
answer
164
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A Baer *-ring which is not embedded into $B(H)$
Assume $A$ is a complex $*$-algebra which is also a Baer*-ring.
Q. Can we concluded that there exists a Hilbert space $H$ such that $A$ is embedded in $B(H)$ as a Baer*-ring? What about when $A$ ...
1
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3
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229
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Some non-trivial Baer *-rings
A Baer *-ring is an *-algebra whose lattice of projections is complete. I know two well-handed kinds of these structures:
1- W*-algebras (abstract case of von Neumann algebras).
2- The inverse ...
1
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1
answer
88
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Two points concerning Baer *-rings
Let $A$ be a unital Baer *-ring.
1- Assume that $\{p_i\}$ is a family of projections in $A$. Let $x$ be an isometry in A (I mean $x^*x=1$ where $1$ is the unit of $A$). True or false: $\inf (...