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20122023
most citedA survey of some norm inequalities

5 citations · 8 across the 7 of their papers we have counts for

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Showing 2021Show all

6 papers · 1 filter

math.FA2021

The Krein-von Neumann Extension of a Regular Even Order Quasi-Differential Operator

Minsung Cho, Seth Hoisington, Roger Nichols +1

We characterize by boundary conditions the Krein-von Neumann extension of a strictly positive minimal operator corresponding to a regular even order quasi-differential expression o…

math.SP2021

Donoghue -functions for singular Sturm--Liouville operators

Fritz Gesztesy, Lance L. Littlejohn, Roger Nichols +2

Let be a densely defined, closed, symmetric operator in the complex, separable Hilbert space with equal deficiency indices and denote by $\mathcal{N}_i = \ke…

math.SP2021★ 3 cited

On Absence of Threshold Resonances for Schrodinger and Dirac Operators

Fritz Gesztesy, Roger Nichols

Using a unified approach employing a homogeneous Lippmann-Schwinger-type equation satisfied by resonance functions and basic facts on Riesz potentials, we discuss the absence of th…

math.SP2021

The limiting absorption principle for massless Dirac operators, properties of spectral shift functions, and an application to the Witten index of non-Fredholm operators

Alan Carey, Fritz Gesztesy, Galina Levitina +3

We derive a limiting absorption principle on any compact interval in for the free massless Dirac operator, in $[L^2(\mathbb…

math.FA2021★ 5 cited

A survey of some norm inequalities

Fritz Gesztesy, Roger Nichols, Jonathan Stanfill

We survey some classical norm inequalities of Hardy, Kallman, Kato, Kolmogorov, Landau, Littlewood, and Rota of the type \[ \|A f\|_{\mathcal{X}}^2 \leq C \|f\|_{\mathcal{X}} \big\…

math.FA2021

The Krein-von Neumann extension revisited

Guglielmo Fucci, Fritz Gesztesy, Klaus Kirsten +3

We revisit the Krein-von Neumann extension in the case where the underlying symmetric operator is strictly positive and apply this to derive the explicit form of the Krein-von Neum…