What is the fractional Laplacian? A comparative review with new results

A Lischke, G Pang, M Gulian, F Song, C Glusa… - Journal of …, 2020 - Elsevier
The fractional Laplacian in R d, which we write as (− Δ) α/2 with α∈(0, 2), has multiple
equivalent characterizations. Moreover, in bounded domains, boundary conditions must be …

Numerical methods for nonlocal and fractional models

M D'Elia, Q Du, C Glusa, M Gunzburger, X Tian… - Acta Numerica, 2020 - cambridge.org
Partial differential equations (PDEs) are used with huge success to model phenomena
across all scientific and engineering disciplines. However, across an equally wide swath …

What is the fractional Laplacian?

A Lischke, G Pang, M Gulian, F Song, C Glusa… - arXiv preprint arXiv …, 2018 - arxiv.org
The fractional Laplacian in R^ d has multiple equivalent characterizations. Moreover, in
bounded domains, boundary conditions must be incorporated in these characterizations in …

Bilevel optimization, deep learning and fractional Laplacian regularization with applications in tomography

H Antil, ZW Di, R Khatri - Inverse Problems, 2020 - iopscience.iop.org
In this work we consider a generalized bilevel optimization framework for solving inverse
problems. We introduce fractional Laplacian as a regularizer to improve the reconstruction …

Fractional operators applied to geophysical electromagnetics

CJ Weiss, BG van Bloemen Waanders… - Geophysical Journal …, 2020 - academic.oup.com
SUMMARY A growing body of applied mathematics literature in recent years has focused on
the application of fractional calculus to problems of anomalous transport. In these analyses …

Spectral approximation of fractional PDEs in image processing and phase field modeling

H Antil, S Bartels - Computational Methods in Applied Mathematics, 2017 - degruyter.com
Fractional differential operators provide an attractive mathematical tool to model effects with
limited regularity properties. Particular examples are image processing and phase field …

Discretizations of the spectral fractional Laplacian on general domains with Dirichlet, Neumann, and Robin boundary conditions

N Cusimano, F del Teso, L Gerardo-Giorda… - SIAM Journal on …, 2018 - SIAM
In this work, we propose novel discretizations of the spectral fractional Laplacian on
bounded domains based on the integral formulation of the operator via the heat-semigroup …

External optimal control of nonlocal PDEs

H Antil, R Khatri, M Warma - Inverse Problems, 2019 - iopscience.iop.org
Abstract Very recently Warma (2019 SIAM J. Control Optim. to appear) has shown that for
nonlocal PDEs associated with the fractional Laplacian, the classical notion of controllability …

A symmetric low-regularity integrator for the nonlinear Schrödinger equation

Y Alama Bronsard - IMA Journal of Numerical Analysis, 2024 - academic.oup.com
We introduce and analyze a symmetric low-regularity scheme for the nonlinear Schrödinger
(NLS) equation beyond classical Fourier-based techniques. We show fractional …

Sobolev spaces with non-Muckenhoupt weights, fractional elliptic operators, and applications

H Antil, CN Rautenberg - SIAM Journal on Mathematical Analysis, 2019 - SIAM
We propose a new variational model in weighted Sobolev spaces with nonstandard weights
and applications to image processing. We show that these weights are, in general, not of …