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Related papers: Iterative initial condition reconstruction

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We present a novel Bayesian method for the joint reconstruction of cosmological matter density fields, peculiar velocities and power-spectra in the quasi-nonlinear regime. We study its applicability to the Ly-alpha forest based on multiple…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Francisco-Shu Kitaura , Simona Gallerani , Andrea Ferrara

Iterative image reconstruction algorithms for optoacoustic tomography (OAT), also known as photoacoustic tomography, have the ability to improve image quality over analytic algorithms due to their ability to incorporate accurate models of…

Analysis of PDEs · Mathematics 2015-06-05 Kun wang , Richard Su , Alexander A. Oraevsky , Mark A. Anastasio

We propose to constrain the primordial (local-type) non-Gaussianity signal by first reconstructing the initial density field to remove the late time non-Gaussianities introduced by gravitational evolution. Our reconstruction algorithm…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-21 Xinyi Chen , Nikhil Padmanabhan , Daniel J. Eisenstein

Dose reduction in computed tomography (CT) is essential for decreasing radiation risk in clinical applications. Iterative reconstruction is one of the most promising ways to compensate for the increased noise due to reduction of photon…

Image and Video Processing · Electrical Eng. & Systems 2021-03-24 Zhuonan He , Yikun Zhang , Yu Guan , Shanzhou Niu , Yi Zhang , Yang Chen , Qiegen Liu

We present and test a new method for the reconstruction of cosmological initial conditions from a full-sky galaxy catalogue. This method, called ZTRACE, is based on a self-consistent solution of the growing mode of gravitational…

Astrophysics · Physics 2009-10-31 P. Monaco , G. Efstathiou

Photoacoustic tomography seeks to reconstruct an acoustic initial pressure distribution from the measurement of the ultrasound waveforms. Conventional methods assume a-prior knowledge of the sound speed distribution, which practically is…

Image and Video Processing · Electrical Eng. & Systems 2019-09-16 Hongming Shan , Christopher Wiedeman , Ge Wang , Yang Yang

Since galaxy distribution reconstruction effectively reduces non-Gaussian terms in the power spectrum covariance matrix, it has attracted interest not only for Baryon Acoustic Oscillation (BAO) signals but also for various cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-16 Naonori Sugiyama

We introduce Back to Basics (BTB), a fast iterative algorithm for noise reduction. Our method is computationally efficient, does not require training or ground truth data, and can be applied in the presence of independent noise, as well as…

Image and Video Processing · Electrical Eng. & Systems 2024-04-19 Deborah Pereg

Acoustic waves traveling through the early Universe imprint a characteristic scale in the clustering of galaxies, QSOs and inter-galactic gas. This scale can be used as a standard ruler to map the expansion history of the Universe, a…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-17 J. D. Cohn , Martin White , Tzu-Ching Chang , Gil Holder , Nikhil Padmanabhan , Olivier Doré

Baryon acoustic oscillations (BAO) underpin the key cosmological results from modern spectroscopic galaxy surveys, but nonlinear gravitational evolution limits the precision achievable with traditional analysis methods. To overcome this, we…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-18 Adrian E. Bayer , Liam Parker , David Valcin , Shi-Fan Chen , Chirag Modi , Uros Seljak

We present a Bayesian reconstruction algorithm to generate unbiased samples of the underlying dark matter field from halo catalogues. Our new contribution consists of implementing a non-Poisson likelihood including a deterministic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Metin Ata , Francisco-Shu Kitaura , Volker Müller

We apply nonlinear reconstruction to the dark matter density field in redshift space and solve for the nonlinear mapping from the initial Lagrangian position to the final redshift space position. The reconstructed anisotropic field inferred…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-13 Hong-Ming Zhu , Yu Yu , Ue-Li Pen

Precise measurements of the baryon acoustic oscillation (BAO) scale as a standard ruler in the clustering pattern of large-scale structure is a central goal of current and future galaxy surveys. The BAO peak may be sharpened using the…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-28 Ixandra Achitouv , Chris Blake

This study presents a noise-robust framework for 1-bit diffraction tomography, a novel imaging approach that relies on intensity-only binary measurements obtained through coded apertures. The proposed reconstruction scheme leverages random…

Information Theory · Computer Science 2025-05-27 Pengwen Chen , Albert Fannjiang

Reconstruction techniques are commonly used in cosmology to reduce complicated nonlinear behaviours to a more tractable linearized system. We study a new reconstruction technique that uses the Moving-Mesh algorithm to estimate the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-21 Qiaoyin Pan , Ue-Li Pen , Derek Inman , Hao-Ran Yu

Image reconstruction in photoacoustic tomography relies on an accurate knowledge of the speed of sound in the target. However, the speed of sound distribution is not generally known, which may result in artefacts in the reconstructed…

Medical Physics · Physics 2025-11-06 Miika Suhonen , Felix Lucka , Aki Pulkkinen , Simon Arridge , Ben Cox , Tanja Tarvainen

Modern digital cameras rely on the sequential execution of separate image processing steps to produce realistic images. The first two steps are usually related to denoising and demosaicking where the former aims to reduce noise from the…

Computer Vision and Pattern Recognition · Computer Science 2019-04-02 Filippos Kokkinos , Stamatios Lefkimmiatis

In light of the evidence for dynamical dark energy (DE) found from the most recent Dark Energy Spectroscopic Instrument (DESI) baryon acoustic oscillation (BAO) measurements, we perform a non-parametric, model-independent reconstruction of…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-18 Maria Berti , Emilio Bellini , Camille Bonvin , Martin Kunz , Matteo Viel , Miguel Zumalacarregui

In this work we propose an objective function to guide the search for a state space reconstruction of a dynamical system from a time series of measurements. This statistics can be evaluated on any reconstructed attractor, thereby allowing a…

Chaotic Dynamics · Physics 2012-05-16 L. C. Uzal , G. L. Grinblat , P. F. Verdes

The next generation of galaxy surveys like the Dark Energy Spectroscopic Instrument (DESI) and Euclid will provide datasets orders of magnitude larger than anything available to date. Our ability to model nonlinear effects in late time…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-15 Atsuhisa Ota , Hee-Jong Seo , Shun Saito , Florian Beutler