C. Fischbacher

activity

20132024

most citedDroplet states in quantum XXZ spin systems on general graphs

12 citations · 22 across the 9 of their papers we have counts for

collaborators

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5 papers · 1 filter

math.FA2020

Extensions of dissipative operators with closable imaginary part

Christoph Fischbacher

Given a dissipative operator $A$ on a complex Hilbert space $H$ such that the quadratic form $f\mapsto \mbox{Im}\langle f,Af\rangle$ is closable, we give a necessary and…

math.FA2018

The Closed Extensions of a Closed Operator

Christoph Fischbacher

Given a densely defined and closed operator $A$ acting on a complex Hilbert space $H$ , we establish a one-to-one correspondence between its closed extensions and subspace…

math.FA2017

A Birman-Krein-Vishik-Grubb theory for sectorial operators

Christoph Fischbacher

We consider densely defined sectorial operators $A_{\pm}$ that can be written in the form $A_{\pm} = \pm i S + V$ with $D (A_{\pm}) = D (S) = D (V)$ , where both $S$ and…

math.FA2017

The Non-Proper Dissipative Extensions of a Dual Pair

Christoph Fischbacher

We consider dissipative operators $A$ of the form $A = S + iV$ , where both $S$ and $V \geq 0$ are assumed to be symmetric but neither of them needs to be (essentially) selfadjoint. Afte…

math.FA2016

The Proper Dissipative Extensions of a Dual Pair

Christoph Fischbacher, Sergey Naboko, Ian Wood

Let $A$ and $(- A)$ be dissipative operators on a Hilbert space $H$ and let $(A, A)$ form a dual pair, i.e. $A \subset A^{*}$ , resp.\ $\wide…