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Parity-odd four-point correlation functions, or trispectra, of cosmic matter density fields provide a unique probe of fundamental symmetries in cosmology. Trispectra of primordial matter density fluctuations produced in the early universe…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-08 Sha Azyzy , Drew Jamieson , Eiichiro Komatsu , Toshiki Kurita

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

I propose to compare the redshift-space density field directly to the REAL-SPACE velocity field. Such a comparison possesses all of the advantages of the conventional redshift-space analyses, while at the same time it is free of their…

Astrophysics · Physics 2007-05-23 Michal Chodorowski

We present an efficient implementation of Wiener filtering of real-space linear field and optimal quadratic estimator of its power spectrum Band-powers. We first recast the field reconstruction into an optimization problem, which we solve…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-16 Benjamin Horowitz , Uros Seljak , Grigor Aslanyan

We measure shifts of the acoustic scale due to nonlinear growth and redshift distortions to a high precision using a very large volume of high-force-resolution simulations. We compare results from various sets of simulations that differ in…

3D dense reconstruction refers to the process of obtaining the complete shape and texture features of 3D objects from 2D planar images. 3D reconstruction is an important and extensively studied problem, but it is far from being solved. This…

Computer Vision and Pattern Recognition · Computer Science 2023-04-20 Yangming Li

In computed tomography (CT), the forward model consists of a linear Radon transform followed by an exponential nonlinearity based on the attenuation of light according to the Beer-Lambert Law. Conventional reconstruction often involves…

Computer Vision and Pattern Recognition · Computer Science 2026-03-25 Sara Fridovich-Keil , Fabrizio Valdivia , Gordon Wetzstein , Benjamin Recht , Mahdi Soltanolkotabi

We present a forward-modelled velocity field reconstruction algorithm that performs the reconstruction of the mass density field using only peculiar velocity data. Our method consistently accounts for the inhomogeneous Malmquist bias using…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-01 Supranta S. Boruah , Guilhem Lavaux , Michael J. Hudson

Very recently a new inversion method has been developped to analyze the intergalactic medium seen in absorption in quasar spectra (the so-called Lyman-alpha forest). This method is applied to recover the temperature of the gas and the…

Deformation gradient tensor fields are reconstructed in three dimensions (mapping all 9 tensor components) using synthetic Dark-Field X-ray Microscopy data. Owing to the unique properties of the microscope, our results imply that the…

Materials Science · Physics 2025-09-09 Axel Henningsson , Sina Borgi , Grethe Winther , Anter El-Azab , Henning Friis Poulsen

Neural implicit reconstruction via volume rendering has demonstrated its effectiveness in recovering dense 3D surfaces. However, it is non-trivial to simultaneously recover meticulous geometry and preserve smoothness across regions with…

Computer Vision and Pattern Recognition · Computer Science 2025-04-09 Ziyu Tang , Weicai Ye , Yifan Wang , Di Huang , Hujun Bao , Tong He , Guofeng Zhang

This work extends the applicability of our recent convexification-based algorithm for constructing images of the dielectric constant of buried or occluded target. We are orientated towards the detection of explosive-like targets such as…

Numerical Analysis · Mathematics 2022-06-22 Vo Anh Khoa , Michael Victor Klibanov , William Grayson Powell , Loc Hoang Nguyen

From the nature of dark matter to the rate of expansion of our Universe, observations of distant galaxies distorted through strong gravitational lensing have the potential to answer some of the major open questions in astrophysics. Modeling…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-18 Siddharth Mishra-Sharma , Ge Yang

The gravitational coupling between large- and small-scale density perturbations leads to anisotropic distortions to the local small-scale matter fluctuations. Such local anisotropic distortions can be used to reconstruct the large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-09 Shi-Hui Zang , Hong-Ming Zhu , Marcel Schmittfull , Ue-Li Pen

We introduce a deep generative framework for high-dimensional Bayesian inference that enables efficient posterior sampling. As telescopes and simulations rapidly expand the volume and resolution of astrophysical data, fast simulation-based…

Instrumentation and Methods for Astrophysics · Physics 2026-03-06 Hadi Sotoudeh , Pablo Lemos , Laurence Perreault-Levasseur

We introduce the eikonal approximation to study the effect of the large-scale motion of cosmic fluids on their small-scale evolution. This approach consists in collecting the impact of the long-wavelength displacement field into a single or…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-09 Francis Bernardeau , Nicolas Van de Rijt , Filippo Vernizzi

We address the problem of inferring the three-dimensional matter distribution from a sparse set of one-dimensional quasar absorption spectra of the Lyman-$\alpha$ forest. Using a Bayesian forward modelling approach, we focus on extending…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Natalia Porqueres , Oliver Hahn , Jens Jasche , Guilhem Lavaux

Characterizing the phase space distribution of particle beams in accelerators is a central part of accelerator understanding and performance optimization. However, conventional reconstruction-based techniques either use simplifying…

Weak lensing measurements are starting to provide statistical maps of the distribution of matter in the universe that are increasingly precise and complementary to cosmic microwave background maps. The probability distribution (PDF)…

Astrophysics · Physics 2009-11-10 Tong-Jie Zhang , Ue-Li Pen

X-ray diffusive dark-field imaging, which allows spatially unresolved microstructure to be mapped across a sample, is an increasingly popular tool in an array of settings. Here, we present a new algorithm for phase and dark-field computed…

Medical Physics · Physics 2023-12-07 T. A. Leatham , D. M. Paganin , K. S. Morgan