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On Riesz decomposition of Volterra operator

Let $T:L^2((0,1)) \to L^2((0,1))$ be the Volterra operator defined by $$ Tf(x) = \int_0^x f(t)\,dt.$$ Given any $\lambda\neq 0$ it is well known that there exists some positive integer $n=n(\lambda)$ ...
Ali's user avatar
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2 votes
0 answers
56 views

Existence of a suitable smooth kernel

Denote by $H=L^2([0,1])$ the Hilbert space of square integrable real valued functions on the interval $[0,1]$. Does there exist a nontrivial smooth real valued function $k$ on the unit interval such ...
Ali's user avatar
  • 4,135
0 votes
1 answer
416 views

Stone–von Neumann theorem?

The Stone–von Neumann theorem says that given two unitary groups on a Hilbert space $H$ satisfying the canonical commutation relations (CCR) $$ U(t)V(s) = e^{-i st} V(s) U(t) \qquad \forall s, t $$ ...
SerkanSüner's user avatar
2 votes
1 answer
467 views

Description of (completely) bounded operator

I am somewhat a beginner in the field of operator algebras and was wondering about the following: Let $T$ be a linear map between the space of bounded operators $B(H)$ on some Hilbert space and $S$ a ...
Hörmander123's user avatar
4 votes
0 answers
298 views

Operator topologies

Let $L(H)$ be the space of bounded operators on some Hilbert space. We can endow this space with the operator norm topology, the strong operator topology (SOT) and the weak operator topology (WOT). ...
Zwars's user avatar
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6 votes
0 answers
210 views

Generalized singular numbers and the Haagerup $L^p$ spaces

Let $M$ be a semi-finite von Neumann algebra with a trace $\tau$.Let $S(M)$ be the algebra of all affiliated operators measurable with respect to $M$. The $L^p$ norm on $M$ is given by \begin{...
Rauan Akylzhanov's user avatar
1 vote
0 answers
102 views

Differentiable Path of Operators and their Inverses

Let $\mathcal{H}$ be a separable Hilbert space. Consider a differentiable map $\mathbb{R} \rightarrow \mathcal{B}(\mathcal{H}), t \mapsto A(t)$, where $\mathcal{B}(\mathcal{H})$ is the space of ...
Clark T.'s user avatar