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Related papers: A Perturbative Approach to the Redshift Space Corr…

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We derive the expression for the observed redshift in the weak field limit in the observer's past light cone, including all relativistic terms up to second order in velocity. We then apply it to compute the cluster-galaxy cross-correlation…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-24 Yan-Chuan Cai , Nick Kaiser , Shaun Cole , Carlos Frenk

Accurate modelling of non-linear scales in galaxy clustering will be crucial for data analysis of Stage IV galaxy surveys. A selection of competing non-linear models must be made based on validation studies. We provide a comprehensive set…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-26 Benjamin Bose , Alkistis Pourtsidou , Katarina Markovič , Florian Beutler

We present a formalism to calculate the non-linear matter power spectrum in modified gravity models that explain the late-time acceleration of the Universe without dark energy. Any successful modified gravity models should contain a…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-03 Kazuya Koyama , Atsushi Taruya , Takashi Hiramatsu

We develop an analytical forward model based on perturbation theory to predict the redshift-space galaxy overdensity at the field level given a realization of the initial conditions. We find that the residual noise between the model and…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-02 Marcel Schmittfull , Marko Simonović , Mikhail M. Ivanov , Oliver H. E. Philcox , Matias Zaldarriaga

Gamma-ray bursts (GRBs) detected at high redshift can be used to trace the cosmic expansion history. However, the calibration of their luminosity distances is not an easy task in comparison to Type Ia Supernovae (SNeIa). To calibrate these…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Celia Escamilla-Rivera , Maryi Carvajal , Cristian Zamora , Martin Hendry

Multivariate time series (MTS) forecasting has shown great importance in numerous industries. Current state-of-the-art graph neural network (GNN)-based forecasting methods usually require both graph networks (e.g., GCN) and temporal…

Machine Learning · Computer Science 2023-11-13 Kun Yi , Qi Zhang , Wei Fan , Hui He , Liang Hu , Pengyang Wang , Ning An , Longbing Cao , Zhendong Niu

Handling big data has largely been a major bottleneck in traditional statistical models. Consequently, when accurate point prediction is the primary target, machine learning models are often preferred over their statistical counterparts for…

Methodology · Statistics 2021-04-02 Arindam Fadikar , Stefan M. Wild , Jonas Chaves-Montero

We compare analytic predictions for real and Fourier space two-point statistics for biased tracers from a variety of Lagrangian Perturbation Theory approaches against those from state of the art N-body simulations in $f(R)$ Hu-Sawicki and…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-29 Georgios Valogiannis , Rachel Bean

We present numerical measurements of the power spectrum response function of the gravitational growth of cosmic structures, defined as the functional derivative of the nonlinear spectrum with respect to the linear counterpart, based on…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-20 Takahiro Nishimichi , Francis Bernardeau , Atsushi Taruya

Modifications of general relativity provide an alternative explanation to dark energy for the observed acceleration of the universe. We calculate quasilinear effects in the growth of structure in f(R) models of gravity using perturbation…

Astrophysics · Physics 2009-10-29 Alex Borisov , Bhuvnesh Jain

We study the dark energy equation of state as a function of redshift in a non-parametric way, without imposing any {\it a priori} $w(z)$ (ratio of pressure over energy density) functional form. As a check of the method, we test our scheme…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Sergey Postnikov , Maria Giovanna Dainotti , Xavier Hernandez , Salvatore Capozziello

Learning dynamical models from data is not only fundamental but also holds great promise for advancing principle discovery, time-series prediction, and controller design. Among various approaches, Gaussian Process State-Space Models…

Machine Learning · Computer Science 2025-10-20 Tengjie Zheng , Haipeng Chen , Lin Cheng , Shengping Gong , Xu Huang

We present a Neural Network based emulator for the galaxy redshift-space power spectrum that enables several orders of magnitude acceleration in the galaxy clustering parameter inference, while preserving 3$\sigma$ accuracy better than…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-03 Svyatoslav Trusov , Pauline Zarrouk , Shaun Cole

Upcoming galaxy redshift surveys promise to significantly improve current limits on primordial non-Gaussianity (PNG) through measurements of 2- and 3-point correlation functions in Fourier space. However, realizing the full potential of…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-19 Azadeh Moradinezhad Dizgah , Matteo Biagetti , Emiliano Sefusatti , Vincent Desjacques , Jorge Noreña

We explore observational constraints on possible deviations from Newtonian gravity by means of large-scale clustering of galaxies. We measure the power spectrum and the bispectrum of Sloan Digital Sky Survey galaxies and compare the result…

Astrophysics · Physics 2008-12-18 Akihito Shirata , Yasushi Suto , Chiaki Hikage , Tetsuya Shiromizu , Naoki Yoshida

Forthcoming radio continuum surveys will cover large volumes of the observable Universe and will reach to high redshifts, making them potentially powerful probes of dark energy, modified gravity and non-Gaussianity. Here we extend recent…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-12 Roy Maartens , Gong-Bo Zhao , David Bacon , Kazuya Koyama , Alvise Raccanelli

Standard sparse pseudo-input approximations to the Gaussian process (GP) cannot handle complex functions well. Sparse spectrum alternatives attempt to answer this but are known to over-fit. We suggest the use of variational inference for…

Machine Learning · Statistics 2015-03-23 Yarin Gal , Richard Turner

It was recently shown that the power spectrum in redshift space can be written as a sum of cross-power spectra between number weighted velocity moments. We investigate the properties of these power spectra for simulated galaxies and dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Teppei Okumura , Uros Seljak , Vincent Desjacques

In this work, we utilize a Gaussian mixture model (GMM) to capture the underlying probability density function (PDF) of the channel trajectories of moving mobile terminals (MTs) within the coverage area of a base station (BS) in an offline…

Signal Processing · Electrical Eng. & Systems 2024-02-14 Nurettin Turan , Benedikt Böck , Kai Jie Chan , Benedikt Fesl , Friedrich Burmeister , Michael Joham , Gerhard Fettweis , Wolfgang Utschick

Testing a subset of viable cosmological models beyond General Relativity (GR), with implications for cosmic acceleration and the Dark Energy associated with it, is within the reach of Rubin Observatory Legacy Survey of Space and Time (LSST)…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-16 Nesar Ramachandra , Georgios Valogiannis , Mustapha Ishak , Katrin Heitmann
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