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相关论文: Precision Analysis of the Local Group Acceleration

200 篇论文

Nonparametric regression models with locally stationary covariates have received increasing interest in recent years. As a nice relief of "curse of dimensionality" induced by large dimension of covariates, additive regression model is…

统计理论 · 数学 2016-12-02 Lixia Hu , Tao Huang , Jinhong You

We present a numerical study of the relation between the cosmic peculiar velocity field and the gravitational acceleration field. We show that on mildly non-linear scales (4-10 Mpc Gaussian smoothing), the distribution of the Cartesian…

This paper presents a Bayesian sampling approach to bandwidth estimation for the local linear estimator of the regression function in a nonparametric regression model. In the Bayesian sampling approach, the error density is approximated by…

统计方法学 · 统计学 2020-11-10 Han Lin Shang , Xibin Zhang

We consider robust covariance estimation with group symmetry constraints. Non-Gaussian covariance estimation, e.g., Tyler scatter estimator and Multivariate Generalized Gaussian distribution methods, usually involve non-convex minimization…

机器学习 · 统计学 2013-06-19 Ilya Soloveychik , Ami Wiesel

Using a diagrammatic approach to Eulerian perturbation theory, we analytically calculate the variance and skewness of the density and velocity divergence induced by gravitational evolution from Gaussian initial conditions, including…

天体物理学 · 物理学 2011-09-30 Roman Scoccimarro , Joshua Frieman

We investigate pointwise estimation of the function-valued velocity field of a second-order linear SPDE. Based on multiple spatially localised measurements, we construct a weighted augmented MLE and study its convergence properties as the…

统计理论 · 数学 2024-02-14 Claudia Strauch , Anton Tiepner

In this work we investigate the nonlinear and nonlocal relation between cosmological density and peculiar velocity fields. Our goal is to provide an algorithm for the recon- struction of the nonlinear velocity field from the fully nonlinear…

宇宙学与河外天体物理 · 物理学 2015-06-03 Francisco-Shu Kitaura , Raul E. Angulo , Yehuda Hoffman , Stefan Gottl"ober

Comparison of peculiar velocities of galaxies with their gravitational accelerations (induced by the density field) is one of the methods to constrain the redshift distortion parameter \beta=(\Omega_m^0.55)/b, where \Omega_m is the…

宇宙学与河外天体物理 · 物理学 2015-02-17 Maciej Bilicki , Michał Chodorowski , Wojciech Hellwing , Thomas Jarrett , Gary Mamon

It has been recently claimed that there is no correlation between the distribution of galaxies and their peculiar velocities within the Local Volume (LV), namely a sphere of R=7/h Mpc around the Local Group (LG). It has been then stated…

天体物理学 · 物理学 2009-06-23 Luis A. Martinez-Vaquero , Gustavo Yepes , Yehuda Hoffman

This paper proposes a novel method to estimate large panel data error-correction models with stationary/non-stationary covariates and spatially dependent errors, which allows for known/unknown group-specific patterns of slope heterogeneity.…

应用统计 · 统计学 2017-09-12 Ba Chu

We analyze a family of non-local integral functionals of convolution-type depending on two small positive parameters $\varepsilon,\delta$: the first rules the length-scale of the non-local interactions and produces a `localization' effect…

偏微分方程分析 · 数学 2025-12-23 Giuseppe Cosma Brusca

A large fraction of cosmological information on dark energy and gravity is encoded in the nonlinear regime. Precision cosmology thus requires precision modeling of nonlinearities in general dark energy and modified gravity models. We modify…

宇宙学与河外天体物理 · 物理学 2014-11-20 Weiguang Cui , Pengjie Zhang , Xiaohu Yang

We study the gravitational influence of very large scale structures, as traced by clusters of galaxies, on the Local Group [LG] motion and the large scale flows. We derive from the distribution of Abell clusters within $300~$Mpc/h the…

天体物理学 · 物理学 2007-05-23 R. Scaramella

We present an improved framework for estimating the growth rate of large-scale structure, using measurements of the galaxy-velocity cross-correlation in configuration space. We consider standard estimators of the velocity auto-correlation…

宇宙学与河外天体物理 · 物理学 2021-02-03 Ryan J. Turner , Chris Blake , Rossana Ruggeri

This paper considers estimating functional-coefficient models in panel quantile regression with individual effects, allowing the cross-sectional and temporal dependence for large panel observations. A latent group structure is imposed on…

计量经济学 · 经济学 2023-03-24 Xiaorong Yang , Jia Chen , Degui Li , Runze Li

We study the lensing convergence power spectrum and its covariance for a standard LCDM cosmology. We run 400 cosmological N-body simulations and use the outputs to perform a total of 1000 independent ray-tracing simulations. We compare the…

宇宙学与河外天体物理 · 物理学 2012-03-12 Masanori Sato , Takashi Hamana , Ryuichi Takahashi , Masahiro Takada , Naoki Yoshida , Takahiko Matsubara , Naoshi Sugiyama

A gauge theory of gravity based on a nonlinear realization (NLR) of the local Conform-Affine (CA) group of symmetry transformations is presented. The coframe fields and gauge connections of the theory are obtained. The tetrads and Lorentz…

广义相对论与量子宇宙学 · 物理学 2008-11-26 S. A. Ali , S. Capozziello

We study evolution of various statistical quantities of smoothed cosmic density and velocity fields using N-body simulations. The parameter $C\equiv <V^2\delta>/(<V^2> <\delta^2>)$ characterizes nonlinear coupling of these two fields and…

天体物理学 · 物理学 2016-08-30 Naoki Seto , Naoshi Sugiyama

The power spectrum of weak lensing fluctuations has a non-Gaussian distribution due to its quadratic nature. On small scales the Central Limit Theorem acts to Gaussianize this distribution but non-Gaussianity in the signal due to…

宇宙学与河外天体物理 · 物理学 2022-06-29 Alex Hall , Andy Taylor

We present a clustering analysis of Luminous Red Galaxies (LRGs) using nearly 9 000 objects from the final catalogue of the 2dF-SDSS LRG And QSO (2SLAQ) Survey. We measure the redshift-space two-point correlation function, xi(s), at the…