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Bayesian field theory denotes a nonparametric Bayesian approach for learning functions from observational data. Based on the principles of Bayesian statistics, a particular Bayesian field theory is defined by combining two models: a…

数据分析、统计与概率 · 物理学 2007-05-23 J. C. Lemm

The ELUCID project aims to build a series of realistic cosmological simulations that reproduce the spatial and mass distribution of the galaxies as observed in the Sloan Digital Sky Survey (SDSS). This requires powerful reconstruction…

宇宙学与河外天体物理 · 物理学 2017-06-06 Dylan Tweed , Xiaohu Yang , Huiyuan Wang , Weiguang Cui , Youcai Zhang , Shijie Li , Y. P. Jing , H. J. Mo

We develop the effective field theory of density fluctuations for a Newtonian self-gravitating N-body system in quasi-equilibrium, apply it to a homogeneous universe with small density fluctuations. Keeping the density fluctuation up to the…

天体物理学 · 物理学 2009-11-13 Yang Zhang , Haixing Miao

N-body simulations are essential for understanding the formation and evolution of structure in the Universe. However, the discrete nature of these simulations affects their accuracy when modelling collisionless systems. We introduce a new…

宇宙学与河外天体物理 · 物理学 2015-11-18 Oliver Hahn , Raul E. Angulo

We present a novel approach for reconstructing the projected mass distribution of clusters of galaxies from sparse and noisy weak gravitational lensing shear data. The reconstructions are regularised using knowledge gained from numerical…

天体物理学 · 物理学 2009-11-24 Phil Marshall

Recently, 3D Gaussian Splatting and its derivatives have achieved significant breakthroughs in large-scale scene reconstruction. However, how to efficiently and stably achieve high-quality geometric fidelity remains a core challenge. To…

计算机视觉与模式识别 · 计算机科学 2026-04-14 Kehua Chen , Tianlu Mao , Xinzhu Ma , Hao Jiang , Zehao Li , Zihan Liu , Shuqin Gao , Honglong Zhao , Feng Dai , Yucheng Zhang , Zhaoqi Wang

We describe the construction of an N-body simulation that mimics the true velocity and mass-density fields in a box of side 256\hmpc about the Local Group , and the production of mock catalogs that mimic in detail current catalogs of…

天体物理学 · 物理学 2009-10-28 Tsafrir Kolatt , Avishai Dekel , Galit Ganon , Jeffrey Willick

3D Gaussian Splatting (3DGS) leverages densely distributed Gaussian primitives for high-quality scene representation and reconstruction. While existing 3DGS methods perform well in scenes with minor view variation, large view changes from…

计算机视觉与模式识别 · 计算机科学 2025-04-29 Chenhao Zhang , Yuanping Cao , Lei Zhang

Building upon the recent pioneering work by Mazenko and by Das and Mazenko, we develop a microscopic, non-equilibrium, statistical field theory for initially correlated canonical ensembles of classical microscopic particles obeying…

统计力学 · 物理学 2019-04-08 Matthias Bartelmann , Felix Fabis , Daniel Berg , Elena Kozlikin , Robert Lilow , Celia Viermann

We present the reconstructed real-space density and the predicted velocity fields from the Two Mass Redshift Survey (2MRS). The 2MRS is the densest all-sky redshift survey to date and includes about 23,200 galaxies with extinction corrected…

We present the first simultaneous analysis of the galaxy overdensity and peculiar velocity fields by modelling their cross-covariance. We apply our new maximum-likelihood approach to data from the 6-degree Field Galaxy Survey (6dFGS), which…

宇宙学与河外天体物理 · 物理学 2017-10-04 Caitlin Adams , Chris Blake

Recent application of the Bayesian algorithm BORG to the Sloan Digital Sky Survey (SDSS) main sample galaxies resulted in the physical inference of the formation history of the observed large-scale structure from its origin to the present…

宇宙学与河外天体物理 · 物理学 2015-06-23 Florent Leclercq , Jens Jasche , Benjamin Wandelt

Multivariate spatial fields are of interest in many applications, including climate model emulation. Not only can the marginal spatial fields be subject to nonstationarity, but the dependence structure among the marginal fields and between…

统计方法学 · 统计学 2023-11-21 Paul F. V. Wiemann , Matthias Katzfuss

We study how to describe collapsed objects, such as galaxies, in the context of the Effective Field Theory of Large Scale Structures. The overdensity of galaxies at a given location and time is determined by the initial tidal tensor,…

宇宙学与河外天体物理 · 物理学 2015-11-11 Leonardo Senatore

Recently, 3D Gaussian Splatting (3DGS) has revolutionized radiance field reconstruction, manifesting efficient and high-fidelity novel view synthesis. However, accurately representing surfaces, especially in large and complex scenarios,…

计算机视觉与模式识别 · 计算机科学 2025-03-05 Yang Liu , Chuanchen Luo , Zhongkai Mao , Junran Peng , Zhaoxiang Zhang

We present N-body cosmological numerical simulations including a primordial non-Gaussianity in the density fluctuation field quantified by the non-linear parameter $f_{NL}$. We have used MPGRAFIC code to produce initial conditions and the…

宇宙学与河外天体物理 · 物理学 2015-05-18 F. Fraschetti , J. M. Alimi , J. Courtin , P. S. Corasaniti

The last few years have seen the development of a promising theoretical framework for statistics of the cosmic large-scale structure -- the theory of large deviations (LDT) for modelling weak-lensing one-point statistics in the mildly…

宇宙学与河外天体物理 · 物理学 2024-01-15 Alexandre Barthelemy , Anik Halder , Zhengyangguang Gong , Cora Uhlemann

A first- and second-order relation between cosmic density and peculiar-velocity fields is presented. The calculation is purely Lagrangian and it is derived using the second-order solutions of the Lagrange-Newton system obtained by Buchert &…

天体物理学 · 物理学 2011-05-23 Mikel Susperregi , Thomas Buchert

Primordial, non-Gaussian perturbations can generate scale-dependent bias in the galaxy distribution. This in turn will modify correlations between galaxy positions and peculiar velocities at late times, since peculiar velocities reflect the…

宇宙学与河外天体物理 · 物理学 2015-06-16 Yin-Zhe Ma , James E. Taylor , Douglas Scott

Galaxies evolve within a web-like cosmic structure, and their properties are strongly shaped by their surrounding environments. We apply a nonparametric Bayesian two-sample test based on P\'olya tree priors to galaxy data from SDSS DR7 and…

星系天体物理 · 物理学 2025-07-24 Ziqi Mu