Christoph Schwerdt

collaborators

4 papers

math.AP2026

Ultracontractivity of Heat semigroups in $L^{2} (I^c ◯)$ with non-local Robin boundary conditions using Nash's inequality

Christoph Schwerdt

We study heat equations $\frac{\partial u}{\partial t} - div (A \nabla u) = 0$ on bounded Lipschitz domains $I^c ◯$ in $R^{d}$ for $d \in \mathbb{…

math.CV2026

Newman's Tauberian theorem, the Riemann-Lebesgue Lemma, and abstract analytic number theory

Jan-Christoph Schlage-Puchta, Christoph Schwerdt

We give a generalized and effective version of Bekehermes' improvement of Newman's Tauberian theorem. To do so we prove an effective version of the Riemann-Lebesgue Lemma for funct…

math.AP2026

Intrinsic Ultracontractivity for a class of Schroedinger Semigroups in $L^{2} (R^{n})$ using Log-Sobolev-inequalities and duality arguments

Christoph Schwerdt, Ilham Ouelddris

We present a class of potentials $q : R^{n} \to (0, \infty)$ that implies the weighted SchrÃ¶dinger semigroup $I ¨ ^{- 1} e^{- t H} I ¨ $ to map a weighted Lebesgue fu…

math.AP2026

Intrinsic Ultracontractivity for a class of Schroedinger Semigroups in $L^{2} (R^{n})$ by Logarithmic Sobolev inequalities

Christoph Schwerdt, Alexander Mill, Dirk Hundertmark

In the first part of this article we present a growth condition on the potential $q$ in the SchrÃ¶dinger operator $H = - I^ + q (x)$ in $L^{2} (R^{n})$ tha…

Ultracontractivity of Heat semigroups in L2(I^c◯) with non-local Robin boundary conditions using Nash's inequality

Newman's Tauberian theorem, the Riemann-Lebesgue Lemma, and abstract analytic number theory

Intrinsic Ultracontractivity for a class of Schroedinger Semigroups in L2(Rn) using Log-Sobolev-inequalities and duality arguments

Intrinsic Ultracontractivity for a class of Schroedinger Semigroups in L2(Rn) by Logarithmic Sobolev inequalities

Ultracontractivity of Heat semigroups in $L^{2} (I^c ◯)$ with non-local Robin boundary conditions using Nash's inequality

Intrinsic Ultracontractivity for a class of Schroedinger Semigroups in $L^{2} (R^{n})$ using Log-Sobolev-inequalities and duality arguments

Intrinsic Ultracontractivity for a class of Schroedinger Semigroups in $L^{2} (R^{n})$ by Logarithmic Sobolev inequalities