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相关论文: A Perturbative Approach to the Redshift Space Corr…

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Expanding upon the work of Way and Srivastava 2006 we demonstrate how the use of training sets of comparable size continue to make Gaussian process regression (GPR) a competitive approach to that of neural networks and other least-squares…

天体物理仪器与方法 · 物理学 2009-11-09 M. J. Way , L. V. Foster , P. R. Gazis , A. N. Srivastava

Starting from first principles, we derive the fundamental equations that relate the $n$-point correlation functions in real and redshift space. Our result generalises the so-called `streaming model' to higher-order statistics: the full…

宇宙学与河外天体物理 · 物理学 2020-07-22 Joseph Kuruvilla , Cristiano Porciani

Accurate photometric redshift estimation is critical for observational cosmology, especially in large-scale surveys where spectroscopic measurements are impractical. Traditional approaches include template fitting and machine learning, each…

天体物理仪器与方法 · 物理学 2026-04-15 Jonas Chris Ferrao , Dickson Dias , Pranav Naik , Glory D'Cruz , Anish Naik , Siya Khandeparkar , Manisha Gokuldas Fal Dessai

Redshift-space distortions (RSD) offer an attractive method to measure the growth of cosmic structure on large scales, and combining with the measurement of the cosmic expansion history, it can be used as cosmological tests of gravity. With…

宇宙学与河外天体物理 · 物理学 2014-10-22 Atsushi Taruya , Kazuya Koyama , Takashi Hiramatsu , Akira Oka

The next generation of galaxy surveys will provide highly accurate measurements of the large-scale structure of the Universe, allowing for more stringent tests of gravity on cosmological scales. Higher order statistics are a valuable tool…

宇宙学与河外天体物理 · 物理学 2023-03-29 Alejandro Aviles , Gustavo Niz

We study Modified Gravity (MG) theories by modelling the redshifted matter power spectrum in a spherical Fourier-Bessel (sFB) basis. We use a fully non-linear description of the real-space matter power-spectrum and include the lowest-order…

宇宙学与河外天体物理 · 物理学 2016-01-27 Dipak Munshi , Geraint Pratten , Patrick Valageas , Peter Coles , Philippe Brax

The large-scale matter distribution in the late-time Universe exhibits gravity-induced non-Gaussianity, and the bispectrum, three-point cumulant is expected to contain significant cosmological information. In particular, the measurement of…

宇宙学与河外天体物理 · 物理学 2017-09-06 Ichihiko Hashimoto , Yann Rasera , Atsushi Taruya

We calculate the dark matter halo correlation function in redshift space using the Gaussian streaming model (GSM). To determine the scale dependent functions entering the streaming model we use local Lagrangian bias together with…

宇宙学与河外天体物理 · 物理学 2016-12-28 Michael Kopp , Cora Uhlemann , Ixandra Achitouv

We present the one-loop 2-point function of biased tracers in redshift space computed with Lagrangian perturbation theory, including a full resummation of both long-wavelength (infrared) displacements and associated velocities. The…

宇宙学与河外天体物理 · 物理学 2021-04-14 Shi-Fan Chen , Zvonimir Vlah , Emanuele Castorina , Martin White

The relation between the galaxy correlation function in real and redshift-space is derived in the linear regime by an appropriate averaging of the joint probability distribution of density and velocity. The derivation recovers the familiar…

天体物理学 · 物理学 2009-10-22 Karl B. Fisher

We propose a method to estimate non-Gaussian error bars on the matter power spectrum from galaxy surveys in the presence of non-trivial survey selection functions. The estimators are often obtained from formalisms like FKP and PKL, which…

宇宙学与河外天体物理 · 物理学 2015-05-30 Joachim Harnois-Deraps , Ue-Li Pen

Measurements of the clustering of galaxies in Fourier space, and at low wavenumbers, offer a window into the early Universe via the possible presence of scale dependent bias generated by Primordial Non Gaussianites. On such large scales a…

宇宙学与河外天体物理 · 物理学 2023-05-08 Emanuele Castorina , Enea di Dio

Accurate modelling of redshift-space distortions (RSD) is challenging in the non-linear regime for two-point statistics e.g. the two-point correlation function (2PCF). We take a different perspective to split the galaxy density field…

宇宙学与河外天体物理 · 物理学 2021-07-14 Enrique Paillas , Yan-Chuan Cai , Nelson Padilla , Ariel Sánchez

We assess the performance of the Taruya, Nishimichi and Saito (TNS) model for the halo redshift space power spectrum, focusing on utilising mildly non-linear scales to constrain the growth rate of structure f. Using simulations with volume…

宇宙学与河外天体物理 · 物理学 2019-11-28 Katarina Markovic , Benjamin Bose , Alkistis Pourtsidou

Subspace-valued functions arise in a wide range of problems, including parametric reduced order modeling (PROM). In PROM, each parameter point can be associated with a subspace, which is used for Petrov-Galerkin projections of large system…

统计理论 · 数学 2021-07-13 Ruda Zhang , Simon Mak , David Dunson

This article characterizes the exact asymptotics of random Fourier feature (RFF) regression, in the realistic setting where the number of data samples $n$, their dimension $p$, and the dimension of feature space $N$ are all large and…

机器学习 · 统计学 2022-01-11 Zhenyu Liao , Romain Couillet , Michael W. Mahoney

Based on the multi-point propagator expansion, we present resummed perturbative calculations for cosmological power spectra and correlation functions in the context of modified gravity. In a wide class of modified gravity models that have a…

宇宙学与河外天体物理 · 物理学 2014-12-17 Atsushi Taruya , Takahiro Nishimichi , Francis Bernardeau , Takashi Hiramatsu , Kazuya Koyama

In this paper, we propose RFF-GP-HSMM, a fast unsupervised time-series segmentation method that incorporates random Fourier features (RFF) to address the high computational cost of the Gaussian process hidden semi-Markov model (GP-HSMM).…

机器学习 · 计算机科学 2025-07-16 Issei Saito , Masatoshi Nagano , Tomoaki Nakamura , Daichi Mochihashi , Koki Mimura

Threshold biasing of a Gaussian random field gives a linear amplification of the reduced two point correlation function at large distances. We show that for standard cosmological models this does not translate into a linear amplification of…

天体物理学 · 物理学 2009-11-07 Ruth Durrer , Andrea Gabrielli , Michael Joyce , Francesco Sylos Labini

The observed power spectrum in redshift space appears distorted due to the peculiar motion of galaxies, known as redshift-space distortions (RSD). While all the effects in RSD are accounted for by the simple mapping formula from real to…

宇宙学与河外天体物理 · 物理学 2018-07-25 Yong-Seon Song , Yi Zheng , Atsushi Taruya , Minji Oh