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相关论文: Increasing Fisher Information by Moving-Mesh Recon…

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We discuss an analytical approximation for the matter power spectrum covariance matrix and its inverse on translinear scales, $k \sim 0.1h - 0.8h/\textrm{Mpc}$ at $z = 0$. We proceed to give an analytical expression for the Fisher…

宇宙学与河外天体物理 · 物理学 2015-08-26 Julien Carron , Melody Wolk , István Szapudi

We present the cosmological distance errors achievable using the baryon acoustic oscillations as a standard ruler. We begin from a Fisher matrix formalism that is upgraded from Seo & Eisenstein (2003). We isolate the information from the…

天体物理学 · 物理学 2011-02-11 Hee-Jong Seo , Daniel J. Eisenstein

We develop a machine learning approach to reconstructing the cosmological initial conditions from late-time dark matter halo number density fields in redshift space, with the goal of improving sensitivity to cosmological parameters, and in…

宇宙学与河外天体物理 · 物理学 2025-08-15 Jelte Bottema , Thomas Flöss , P. Daniel Meerburg

The quality of numerical reconstructions for unknown parameters in inverse problems depends fundamentally on the selection of experimental data. To ensure a robust reconstruction, it is crucial to select data that are sensitive to the…

数值分析 · 数学 2026-04-14 Kathrin Hellmuth , Christian Klingenberg , Qin Li

We apply an iterative reconstruction method to galaxy mocks in redshift space obtained from $N$-body simulations. Comparing the two-point correlation functions for the reconstructed density field, we find that although the performance is…

宇宙学与河外天体物理 · 物理学 2019-06-26 Ryuichiro Hada , Daniel J. Eisenstein

In this paper, we propose a unified energy minimization model for the segmentation of non-smooth image structures. The energy of piecewise linear patch reconstruction is considered as an objective measure of the quality of the segmentation…

计算机视觉与模式识别 · 计算机科学 2014-04-08 Junyan Wang , Kap Luk Chan

This paper presents a novel method for the reconstruction of images from samples located at non-integer positions, called mesh. This is a common scenario for many image processing applications, such as super-resolution, warping or virtual…

计算机视觉与模式识别 · 计算机科学 2022-05-23 Ján Koloda , Jürgen Seiler , André Kaup

We find that nonlinearities in the dark-matter power spectrum are dramatically smaller if the density field first undergoes a logarithmic mapping. In the Millennium simulation, this procedure produces a power spectrum with a shape hardly…

宇宙学与河外天体物理 · 物理学 2011-02-11 Mark C. Neyrinck , István Szapudi , Alexander S. Szalay

One of the main unsolved problems of cosmology is how to maximize the extraction of information from nonlinear data. If the data are nonlinear the usual approach is to employ a sequence of statistics (N-point statistics, counting statistics…

宇宙学与河外天体物理 · 物理学 2018-03-07 Uros Seljak , Grigor Aslanyan , Yu Feng , Chirag Modi

We quantify the performance of a non-linear Wiener filter, constructed in wavelet space, at recovering some of the Fisher information that was lost in the weak lensing convergence field. The proposed method consists in a separation of the…

宇宙学与河外天体物理 · 物理学 2011-12-16 Hao-Ran Yu , Joachim Harnois-Déraps , Tong-Jie Zhang , Ue-Li Pen

The microstructure analyses of porous media have considerable research value for the study of macroscopic properties. As the premise of conducting these analyses, the accurate reconstruction of microstructure digital model is also an…

图像与视频处理 · 电气工程与系统科学 2023-04-26 Zhenchuan Ma , Xiaohai He , Pengcheng Yan , Fan Zhang , Qizhi Teng

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…

宇宙学与河外天体物理 · 物理学 2016-09-23 Hong-Ming Zhu , Ue-Li Pen , Xuelei Chen

The reconstruction of the initial conditions of the Universe is an important topic in cosmology, particularly in the context of sharpening the measurement of the baryon acoustic oscillation (BAO) peak. Nonlinear reconstruction algorithms…

宇宙学与河外天体物理 · 物理学 2018-12-19 Jack Birkin , Baojiu Li , Marius Cautun , Yanlong Shi

We consider the inverse problem of retrieving aerosol extinction coefficients from Raman lidar measurements. In this problem the unknown and the data are related through the exponential of a linear operator, the unknown is non-negative and…

数值分析 · 数学 2018-08-21 Giulia Denevi , Sara Garbarino , Alberto Sorrentino

We study the use of U-Nets in reconstructing the linear dark matter density field and its consequences for constraining cosmological parameters, in particular primordial non-Gaussianity. Our network is able to reconstruct the initial…

宇宙学与河外天体物理 · 物理学 2024-02-23 Thomas Flöss , P. Daniel Meerburg

This paper presents a new iterative reconstruction method to provide high-resolution images of shear modulus and viscosity via the internal measurement of displacement fields in tissues. To solve the inverse problem, we compute the…

偏微分方程分析 · 数学 2017-02-10 Habib Ammari , Jin Keun Seo , Liangdong Zhou

Next-generation spectroscopic surveys such as the MegaMapper, MUltiplexed Survey Telescope (MUST), MaunaKea Spectroscopic Explorer (MSE), and Wide Spectroscopic Telescope (WST) are foreseen to increase the number of galaxy/quasar redshifts…

宇宙学与河外天体物理 · 物理学 2024-01-11 William d'Assignies D. , Cheng Zhao , Jiaxi Yu , Jean-Paul Kneib

Defect reconstruction is essential in non-destructive testing and structural health monitoring with guided ultrasonic waves. This paper presents an algorithm for reconstructing notches in steel plates which can be seen as artificial defects…

数值分析 · 数学 2023-06-06 Jannis Bulling , Benjamin Jurgelucks , Jens Prager , Andrea Walther

We present a same-level comparison of the most prominent inversion methods for the reconstruction of the matter density field in the quasi-linear regime from the Ly$\alpha$ forest flux. Moreover, we present a pathway for refining the…

宇宙学与河外天体物理 · 物理学 2020-08-12 Hendrik Müller , Christoph Behrens , David James Edward Marsh

We explore the covariance of redshift-space matter power spectra after a standard density-field reconstruction. We derive perturbative formula of the covariance at the tree-level order and find that the amplitude of the off-diagonal…

宇宙学与河外天体物理 · 物理学 2020-10-14 Chiaki Hikage , Ryuichi Takahashi , Kazuya Koyama