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Related papers: Iterative initial condition reconstruction

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The main aim of this paper is to perform a model comparison for some reconstructions of the key properties that describe the dark energy of the Universe i.e. energy density and the equation of state (EoS). We carry out this process by using…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-28 Luis A. Escamilla , J. Alberto Vazquez

The Baryon Acoustic Oscillations (BAO) in the large-scale structure of the universe leave a distinct peak in the two-point correlation function of the matter distribution. That acoustic peak is smeared and shifted by bulk flows and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Svetlin Tassev , Matias Zaldarriaga

We present a new method to reconstruct the primordial (linear) density field using the estimated nonlinear displacement field. The divergence of the displacement field gives the reconstructed density field. We solve the nonlinear…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-23 Hong-Ming Zhu , Ue-Li Pen , Xuelei Chen

Reconstructing an estimate of linear Baryon Acoustic Oscillations (BAO) from an evolved galaxy field has become a standard technique in recent analyses. By partially removing non-linear damping caused by bulk motions, the real-space BAO…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-26 Angela Burden , Will J. Percival , Marc Manera , Antonio J. Cuesta , Mariana Vargas Magana , Shirley Ho

In this paper we consider the problem of acoustic inversion in the context of the optoacoustic tomography image reconstruction problem. By leveraging the ability of the recently proposed diffusion models for image generative tasks among…

Image and Video Processing · Electrical Eng. & Systems 2024-04-17 M. G. González , M. Vera , A. Dreszman , L. J. Rey Vega

We present a direct approach to nonparametrically reconstruct the linear density field from an observed nonlinear map. We solve for the unique displacement potential consistent with the nonlinear density and positive definite coordinate…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-25 Hong-Ming Zhu , Yu Yu , Ue-Li Pen , Xuelei Chen , Hao-Ran Yu

Gravitational non-linear evolution induces a shift in the position of the baryon acoustic oscillations (BAO) peak together with a damping and broadening of its shape that bias and degrades the accuracy with which the position of the peak…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-12 Andrej Obuljen , Francisco Villaescusa-Navarro , Emanuele Castorina , Matteo Viel

A commonly used perturbative method for computing large-scale clustering of tracers of mass density, like galaxies, is to model the tracer density field as a Taylor series in the local smoothed mass density fluctuations, possibly adding a…

Astrophysics · Physics 2014-10-13 Patrick McDonald

Applying standard algorithms to sparse data problems in photoacoustic tomography (PAT) yields low-quality images containing severe under-sampling artifacts. To some extent, these artifacts can be reduced by iterative image reconstruction…

Numerical Analysis · Mathematics 2024-12-20 Stephan Antholzer , Johannes Schwab , Robert Nuster , Markus Haltmeier

We present a Bayesian reconstruction algorithm that infers the three-dimensional large-scale matter distribution from the weak gravitational lensing effects measured in the image shapes of galaxies. The algorithm is designed to also work…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-20 Vanessa Böhm , Stefan Hilbert , Maksim Greiner , Torsten A. Enßlin

Density-reconstruction sharpens the baryon acoustic oscillations signal by undoing some of the smoothing incurred by nonlinear structure formation. In this paper we present an analytical model for reconstruction based on the Zeldovich…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-18 Shi-Fan Chen , Zvonimir Vlah , Martin White

This paper investigates the simultaneous identification of a spatially dependent potential and the initial condition in a subdiffusion model based on two terminal observations. The existence, uniqueness, and conditional stability of the…

Numerical Analysis · Mathematics 2025-10-28 Xu Wu , Jiang Yang , Zhi Zhou

Reconstructing cosmological initial conditions (ICs) from late-time observations is a difficult task, which relies on the use of computationally expensive simulators alongside sophisticated statistical methods to navigate multi-million…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-22 Oleg Savchenko , Florian List , Guillermo Franco Abellán , Noemi Anau Montel , Christoph Weniger

We further develop the description of redshift space distortions within the Effective Field Theory of Large Scale Structures. First, we generalize the counterterms to include the effect of baryonic physics and primordial non-Gaussianity.…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Matthew Lewandowski , Leonardo Senatore , Francisco Prada , Cheng Zhao , Chia-Hsun Chuang

For lossy image compression systems, we develop an algorithm, iterative refinement, to improve the decoder's reconstruction compared to standard decoding techniques. Specifically, we propose a recurrent neural network approach for…

Computer Vision and Pattern Recognition · Computer Science 2018-11-13 Alexander G. Ororbia , Ankur Mali , Jian Wu , Scott O'Connell , David Miller , C. Lee Giles

Initial density distribution provides a basis for understanding the complete evolution of cosmological density fluctuations. While reconstruction in our local Universe exploits the observations of galaxy surveys with large volumes,…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-28 Meng Zhou , Yi Mao

Future Baryon Acoustic Oscillation surveys aim at observing galaxy clustering over a wide range of redshift and galaxy populations at great precision, reaching tenths of a percent, in order to detect any deviation of dark energy from the…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-31 Zhejie Ding , Hee-Jong Seo , Zvonimir Vlah , Yu Feng , Marcel Schmittfull , Florian Beutler

Optoacoustic tomography image reconstruction has been a problem of interest in recent years. By exploiting the exceptional generative power of the recently proposed diffusion models we consider a scheme which is based on a conditional…

Image and Video Processing · Electrical Eng. & Systems 2024-11-26 Martin G. Gonzalez , Matias Vera , Leonardo Rey Vega

Objective: Quantitative technique based on In-line phase-contrast computed tomography with single scanning attracts more attention in application due to the flexibility of the implementation. However, the quantitative results usually suffer…

Medical Physics · Physics 2022-06-13 Suyu Liao , Shiwo Deng , Yining Zhu , Huitao Zhang , Peiping Zhu , Kai Zhang , Xing Zhao

We review the different approaches for combining the cosmological information from the full shape of the pre-reconstructed power spectrum - usually referred as redshift-space distortion (RSD) analysis - and from the baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-01 Héctor Gil-Marín