3 papers
math.NA2025
Projected iterated Tikhonov regularization in low precision
Chelsea Drum, James. G. Nagy, Lucas Onisk
We investigate the regularizing behavior of an iterative Krylov subspace method for the solution of linear inverse problems in precisions lower than double. Recent works have consi…
math.NA2025
Iterative Refinement and Flexible Iteratively Reweighed Solvers for Linear Inverse Problems with Sparse Solutions
Lucas Onisk, Malena Sabaté Landman
This paper presents a new algorithmic framework for computing sparse solutions to large-scale linear discrete ill-posed problems. The approach is motivated by recent perspectives o…
math.NA2024
Iterative Reconstruction Methods for Cosmological X-Ray Tomography
Julianne Chung, Lucas Onisk, Yiran Wang
We consider the imaging of cosmic strings by using Cosmic Microwave Background (CMB) data. Mathematically, we study the inversion of an X-ray transform in Lorentzian geometry, call…