Generative modelling for mass-mapping with fast uncertainty quantification

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Whitney, Jessica J., Liaudat, Tobías I., Price, Matthew A., Mars, Matthijs, McEwen, Jason D.
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915544096047104
author Whitney, Jessica J.
Liaudat, Tobías I.
Price, Matthew A.
Mars, Matthijs
McEwen, Jason D.
author_facet Whitney, Jessica J.
Liaudat, Tobías I.
Price, Matthew A.
Mars, Matthijs
McEwen, Jason D.
contents Understanding the nature of dark matter in the Universe is an important goal of modern cosmology. A key method for probing this distribution is via weak gravitational lensing mass-mapping - a challenging ill-posed inverse problem where one infers the convergence field from observed shear measurements. Upcoming stage IV surveys, such as those made by the Vera C. Rubin Observatory and Euclid satellite, will provide a greater quantity and precision of data for lensing analyses, necessitating high-fidelity mass-mapping methods that are computationally efficient and that also provide uncertainties for integration into downstream cosmological analyses. In this work we introduce MMGAN, a novel mass-mapping method based on a regularised conditional generative adversarial network (GAN) framework, which generates approximate posterior samples of the convergence field given shear data. We adopt Wasserstein GANs to improve training stability and apply regularisation techniques to overcome mode collapse, issues that otherwise are particularly acute for conditional GANs. We train and validate our model on a mock COSMOS-style dataset before applying it to true COSMOS survey data. Our approach significantly outperforms the Kaiser-Squires technique and achieves similar reconstruction fidelity as alternative state-of-the-art deep learning approaches. Notably, while alternative approaches for generating samples from a learned posterior are slow (e.g. requiring $\sim$10 GPU minutes per posterior sample), MMGAN can produce a high-quality convergence sample in less than a second.
format Preprint
id arxiv_https___arxiv_org_abs_2410_24197
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Generative modelling for mass-mapping with fast uncertainty quantification
Whitney, Jessica J.
Liaudat, Tobías I.
Price, Matthew A.
Mars, Matthijs
McEwen, Jason D.
Cosmology and Nongalactic Astrophysics
Instrumentation and Methods for Astrophysics
Understanding the nature of dark matter in the Universe is an important goal of modern cosmology. A key method for probing this distribution is via weak gravitational lensing mass-mapping - a challenging ill-posed inverse problem where one infers the convergence field from observed shear measurements. Upcoming stage IV surveys, such as those made by the Vera C. Rubin Observatory and Euclid satellite, will provide a greater quantity and precision of data for lensing analyses, necessitating high-fidelity mass-mapping methods that are computationally efficient and that also provide uncertainties for integration into downstream cosmological analyses. In this work we introduce MMGAN, a novel mass-mapping method based on a regularised conditional generative adversarial network (GAN) framework, which generates approximate posterior samples of the convergence field given shear data. We adopt Wasserstein GANs to improve training stability and apply regularisation techniques to overcome mode collapse, issues that otherwise are particularly acute for conditional GANs. We train and validate our model on a mock COSMOS-style dataset before applying it to true COSMOS survey data. Our approach significantly outperforms the Kaiser-Squires technique and achieves similar reconstruction fidelity as alternative state-of-the-art deep learning approaches. Notably, while alternative approaches for generating samples from a learned posterior are slow (e.g. requiring $\sim$10 GPU minutes per posterior sample), MMGAN can produce a high-quality convergence sample in less than a second.
title Generative modelling for mass-mapping with fast uncertainty quantification
topic Cosmology and Nongalactic Astrophysics
Instrumentation and Methods for Astrophysics
url https://arxiv.org/abs/2410.24197