Bernhard H. Haak

activity

20062026

most citedMathematical Analysis of the Motion of a Rigid Body in a Compressible Navier-Stokes-Fourier Fluid

24 citations · 60 across the 15 of their papers we have counts for

collaborators

20 papers

math.AP2026

Curved Ingham Inequalities for Dispersive Trigonometric Sums

Bernhard H Haak, Philippe Jaming, Ming Wang +1

We study $L^{2}$ restrictions of dispersive trigonometric sums $F (t, x) = n \in Z \sum c_{n} e^{2 π i (∣ n ∣^{s} t + n x)}$ to curves in the $(t, x)$ -plane. Our main result is a curved analogue…

math.FA2025

A cheap way to closed operator sums

Bernhard H. Haak, Peer Christian Kunstmann

Let $A$ and $B$ be sectorial operators in a Banach space $X$ of angles $ω_{A}$ and $ω_{B}$ , respectively, where $ω_{A} + ω_{B} < π$ . We present a simple and common approach to results on close…

math.FA2025

A weak type $(p, a)$ criterion for operators, and applications

Bernhard H. Haak, El-Maati Ouhabaz

Let $(X, d, μ)$ be a space of homogeneous type and $Ω$ an open subset of $X$ . Given a bounded operator $T : L^{p} (Ω) \to L^{q} (Ω)$ for some $1 \leq p \leq q < \infty$ , we give a criterion…

math.FA2024

Vector-Valued Holomorphic Functions and Abstract Fubini-Type Theorems

Bernhard H. Haak, Markus Haase

Let $f = f (z, t)$ be a function holomorphic in $z \in O \subseteq C^{d}$ for fixed $t \in Ω$ and measurable in $t$ for fixed $z$ and such that $z \mapsto f (z, \cdot)$ is bounde…

math.FA2023

Remarks on Ritt operators, their $H^{\infty}$ functional calculus and associated square function estimates

Bernhard H. Haak

This note deals with the boundedness of the $H^{\infty}$ functional calculus of Ritt operators $T$ and associated square function estimates. The purpose is to give a shorter, concise…

math.AP2018

Controllability and observability for non-autonomous evolution equations: the averaged Hautus test

Bernhard Haak, Duc-Trung Hoang, El-Maati Ouhabaz

We consider the observability problem for non-autonomous evolution systems (i.e., the operators governing the system depend on time). We introduce an averaged Hautus condition and…