Reconstruction of the observable universe from the integrated Sachs-Wolfe effect
Mathematical Physics
2025-07-03 v1 Numerical Analysis
math.MP
Numerical Analysis
Abstract
The integrated Sachs-Wolfe (ISW) effect is a property of the Cosmic Microwave Background (CMB), in which photons from the CMB are gravitationally redshifted, causing the anisotropies in the CMB. An intriguing question is whether one can infer the gravitational perturbations from the ISW effect observed near the Earth. In this work, we address the question using a tomographic reconstruction approach, similar to X-ray CT reconstruction in medical imaging. We develop the mathematical analysis for the stable inversion of the X-ray transform in the cosmological setting. In addition, we provide a numerical study of reconstruction methods, thereby demonstrating the feasibility and potential of the tomography method.
Keywords
Cite
@article{arxiv.2507.01399,
title = {Reconstruction of the observable universe from the integrated Sachs-Wolfe effect},
author = {Julianne Chung and Yiran Wang},
journal= {arXiv preprint arXiv:2507.01399},
year = {2025}
}