activity
20132026
most citedUnique Continuation for Fractional Schrödinger Equations with Rough Potential

88 citations · 134 across the 22 of their papers we have counts for

collaborators

26 papers

math.AP2026

Instability estimates for the recovery of absorption in the diffusive regime of radiative transfer

Elena Demattè, Alessandro Felisi, Angkana Rüland +1

We revisit the instability properties of the recovery of the absorption coefficient for the radiative transfer equation in the diffusive regime. To this end, we develop a rather ro…

math.AP2026

On the transfer of stability from the local to the fractional anisotropic Calderón problem with exterior measurements

Hendrik Baers, Angkana Rüland

We study the quantitative transfer of uniqueness from the classical to the fractional Calderón problem with exterior data. This allows us to deduce the first stability estimates fo…

math.AP2025

Transfer of Stability from the Classical to the Fractional Anisotropic Calderón Problem

Hendrik Baers, Angkana Rüland

We discuss two spectral fractional anisotropic Calderón problems with source-to-solution measurements and their quantitative relation to the classical Calderón problem. Firstly, we…

math.AP2025

On surface energies in scaling laws for singular perturbation problems for martensitic phase transitions

Angkana Rüland, Camillo Tissot, Antonio Tribuzio +1

The objective of this article is to compare different surface energies for multi-well singular perturbation problems associated with martensitic phase transformations involving hig…

math.AP2025

Boundary Reconstruction for the Anisotropic Fractional Calderón Problem

Xiaopeng Cheng, Angkana Rüland

In this article, we provide a boundary reconstruction result for the anisotropic fractional Calderón problem and its associated degenerate elliptic extension into the upper half pl…

math.AP2025

Fractional anisotropic Calderón problem with external data

Ali Feizmohammadi, Tuhin Ghosh, Katya Krupchyk +3

In this paper, we solve the fractional anisotropic Calderón problem with external data in the Euclidean space, in dimensions two and higher, for smooth Riemannian metrics that agre…

math.AP2024

On a -Structure in Geometrically Linearized Elasticity: Qualitative and Quantitative Analysis and Numerical Simulations

Roman Indergand, Dennis Kochmann, Angkana Rüland +2

We study the rigidity properties of the -structure for the symmetrized gradient from \cite{BFJK94} qualitatively, quantitatively and numerically. More precisely, we complement…

math.AP2024

On Instability Properties of the Fractional Calderón Problem

Hendrik Baers, Giovanni Covi, Angkana Rüland

We prove exponential instability properties for the fractional Calderón problem and the conductivity formulation of the fractional Calderón problem in the regime of fractional powe…

math.AP2024

On the Effect of Geometry on Scaling Laws for a Class of Martensitic Phase Transformations

Janusz Ginster, Angkana Rüland, Antonio Tribuzio +1

We study scaling laws for singular perturbation problems associated with a class of two-dimensional martensitic phase transformations and deduce a domain dependence of the scaling…

math.AP2023

Revisiting the Anisotropic Fractional Calderón Problem Using the Caffarelli-Silvestre Extension

Angkana Rüland

We revisit the source-to-solution anisotropic fractional Calderón problem introduced and analyzed in [FGKU21] and [F21]. Using the Caffarelli-Silvestre interpretation of the fracti…

math.AP2023

A Reduction of the Fractional Calderón Problem to the Local Calderón Problem by Means of the Caffarelli-Silvestre Extension

Giovanni Covi, Tuhin Ghosh, Angkana Rüland +1

We relate the (anisotropic) variable coefficient local and nonlocal Calderón problems by means of the Caffarelli-Silvestre extension. In particular, we prove that (partial) Dirichl…

math.AP2022

On (Global) Unique Continuation Properties of the Fractional Discrete Laplacian

Aingeru Fernández-Bertolin, Luz Roncal, Angkana Rüland

We study various qualitative and quantitative (global) unique continuation properties for the fractional discrete Laplacian. We show that while the fractional Laplacian enjoys stri…

math.AP2021

Runge Approximation and Stability Improvement for a Partial Data Calderón Problem for the Acoustic Helmholtz Equation

María Ángeles García-Ferrero, Angkana Rüland, Wiktoria Zatoń

In this article, we discuss quantitative Runge approximation properties for the acoustic Helmholtz equation and prove stability improvement results in the high frequency limit for…

math.AP2019

Convex Integration Solutions for the Geometrically Non-linear Two-Well Problem with Higher Sobolev Regularity

Francesco Della Porta, Angkana Rüland

In this article we discuss higher Sobolev regularity of convex integration solutions for the geometrically non-linear two-well problem. More precisely, we construct solutions to th…

math.AP2019★ 3 cited

Strong unique continuation for the higher order fractional Laplacian

María-Ángeles García-Ferrero, Angkana Rüland

In this article we study the strong unique continuation property for solutions of higher order (variable coefficient) fractional Schrödinger operators. We deduce the strong unique…

math.AP2018★ 1 cited

On the Fractional Landis Conjecture

Angkana Rüland, Jenn-Nan Wang

In this paper we study a Landis-type conjecture for fractional Schrödinger equations of fractional power with potentials. We discuss both the cases of differentiable an…

math.AP2018★ 1 cited

Lipschitz stability for the Finite Dimensional Fractional Calderón Problem with Finite Cauchy Data

Angkana Rüland, Eva Sincich

In this note we discuss the conditional stability issue for the finite dimensional Calderón problem for the fractional Schrödinger equation with a finite number of measurements. Mo…

math.AP2018

Unique Continuation for Sublinear Elliptic Equations Based on Carleman Estimates

Angkana Rüland

In this article we deal with different forms of the unique continuation property for second order elliptic equations with nonlinear potentials of sublinear growth. Under suitable r…

math.AP2017

Quantitative Runge Approximation and Inverse Problems

Angkana Rüland, Mikko Salo

In this short note we provide a quantitative version of the classical Runge approximation property for second order elliptic operators. This relies on quantitative unique continuat…

math.AP2017

Quantitative Approximation Properties for the Fractional Heat Equation

Angkana Rüland, Mikko Salo

In this note we analyse \emph{quantitative} approximation properties of a certain class of \emph{nonlocal} equations: Viewing the fractional heat equation as a model problem, which…

math.AP2017

Quantitative Invertibility and Approximation for the Truncated Hilbert and Riesz Transforms

Angkana Rüland

In this article we derive quantitative uniqueness and approximation properties for (perturbations) of Riesz transforms. Seeking to provide robust arguments, we adopt a PDE point of…

math.AP2016★ 9 cited

Higher Regularity for the fractional thin obstacle problem

Herbert Koch, Angkana Rüland, Wenhui Shi

In this article we investigate the higher regularity properties of the regular free boundary in the fractional thin obstacle problem. Relying on a Hodograph-Legendre transform, we…

math.AP2016★ 6 cited

The Variable Coefficient Thin Obstacle Problem: Higher Regularity

Herbert Koch, Angkana Rüland, Wenhui Shi

In this article we continue our investigation of the thin obstacle problem with variable coefficients which was initiated in \cite{KRS14}, \cite{KRSI}. Using a partial Hodograph-Le…

math.AP2013★ 88 cited

Unique Continuation for Fractional Schrödinger Equations with Rough Potential

Angkana Rüland

This article deals with the weak and strong unique continuation principle for fractional Schrödinger equations with scaling-critical and rough potentials via Carleman estimates. Ou…