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Related papers: An iterative reconstruction of cosmological initia…

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Reconstructing cosmological initial conditions (ICs) from late-time observations is a difficult task, which relies on the use of computationally expensive simulators alongside sophisticated statistical methods to navigate multi-million…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-22 Oleg Savchenko , Florian List , Guillermo Franco Abellán , Noemi Anau Montel , Christoph Weniger

We present a hybrid method for reconstructing the primordial density from late-time halos and galaxies. Our approach involves two steps: (1) apply standard Baryon Acoustic Oscillation (BAO) reconstruction to recover the large-scale features…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-03 Liam Parker , Adrian E. Bayer , Uros Seljak

The COSMOS field has been the subject of a wide range of observations, with a number of studies focusing on reconstructing the 3D dark matter density field. Typically, these studies have focused on one given method or tracer. In this paper,…

We model a 21 cm intensity mapping survey in the redshift range 0.01<z<1.5 designed to simulate the skies as seen by future radio telescopes such as the Square Kilometre Array (SKA), including instrumental noise and Galactic foregrounds. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-27 L. Wolz , F. B. Abdalla , C. Blake , J. R. Shaw , E. Chapman , S. Rawlings

Gravitational lensing distorts the cosmic microwave background (CMB) anisotropies and imprints a characteristic pattern onto it. The distortions depend on the projected matter density between today and redshift $z \sim 1100$. In this paper…

Astrophysics · Physics 2016-08-25 Matias Zaldarriaga , Uros Seljak

The large-scale structure is a major source of cosmological information. However, next-generation photometric galaxy surveys will only provide a distorted view of cosmic structures due to large redshift uncertainties. To address the need…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-10 Eleni Tsaprazi , Jens Jasche , Guilhem Lavaux , Florent Leclercq

We present a method to reconstruct the initial conditions of the universe using observed galaxy positions and luminosities under the assumption that the luminosities can be calibrated with weak lensing to give the mean halo mass. Our method…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-24 Chirag Modi , Yu Feng , Uros Seljak

Redshift space distortions of the matter density power spectrum carry information on the growth rate of cosmic structure but require accurate modeling of nonlinear and velocity effects on the density field. We test and advance the…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-19 Alberto Vallinotto , Eric V. Linder

We present a direct approach to nonparametrically reconstruct the linear density field from an observed nonlinear map. We solve for the unique displacement potential consistent with the nonlinear density and positive definite coordinate…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-25 Hong-Ming Zhu , Yu Yu , Ue-Li Pen , Xuelei Chen , Hao-Ran Yu

The gravitational coupling between large-scale perturbations and small-scale perturbations leads to anisotropic distortions of the small-scale matter distribution. The measured local small-scale power spectrum can thus be used to infer the…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Hong-Ming Zhu , Tian-Xiang Mao , Ue-Li Pen

Low redshift measurements of Baryon Acoustic Oscillations (BAO) test the late time evolution of the Universe and are a vital probe of Dark Energy. Over the past decade both the 6-degree Field Galaxy Survey (6dFGS) and Sloan Digital Sky…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 Paul Carter , Florian Beutler , Will J. Percival , Chris Blake , Jun Koda , Ashley J. Ross

The density field reconstruction technique has been widely used for recovering the Baryon Acoustic Oscillation (BAO) feature in galaxy surveys that has been degraded due to nonlinearities. Recent studies advocated adopting iterative steps…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-02 Hee-Jong Seo , Atsuhisa Ota , Marcel Schmittfull , Shun Saito , Florian Beutler

Reconstructing the initial conditions of the universe is a key problem in cosmology. Methods based on simulating the forward evolution of the universe have provided a way to infer initial conditions consistent with present-day observations.…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-11 Ronan Legin , Matthew Ho , Pablo Lemos , Laurence Perreault-Levasseur , Shirley Ho , Yashar Hezaveh , Benjamin Wandelt

We obtain approximations for the CDM particle trajectories starting from Lagrangian Perturbation Theory. These estimates for the CDM trajectories result in approximations for the density in real and redshift space, as well as for the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Svetlin Tassev , Matias Zaldarriaga

The gravitational coupling of a long-wavelength tidal field with small-scale density fluctuations leads to anisotropic distortions of the locally measured small-scale matter correlation function. Since the local correlation function is…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-25 Hong-Ming Zhu , Ue-Li Pen , Yu Yu , Xinzhong Er , Xuelei Chen

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…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-23 Hong-Ming Zhu , Ue-Li Pen , Xuelei Chen

The Baryon Acoustic Oscillation (BAO) feature, imprinted in the transverse and radial clustering of dark matter tracers, enables the simultaneous measurement of the angular diameter distance $D_A(z)$ and the Hubble parameter $H(z)$ at a…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-08 Pankaj Chavan , Tapomoy Guha Sarkar , Anjan A Sen

We present a method for reconstructing cosmological densityn for and velocity fields using the Lagrangian Zel'dovich formalism. . The method involves finding the least action solution for straight line particle paths in an evolving density…

Astrophysics · Physics 2015-06-24 R. A. C. Croft , E. Gaztanaga

The gravitational coupling between large- and small-scale density perturbations leads to anisotropic distortions to the local small-scale matter fluctuations. Such local anisotropic distortions can be used to reconstruct the large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-09 Shi-Hui Zang , Hong-Ming Zhu , Marcel Schmittfull , Ue-Li Pen

Baryonic acoustic oscillations imprinted in the galaxy power spectrum provide a promising tool for probing the cosmological distance scale and dark energy. We present results from a suite of cosmological N-body simulations aimed at…

Astrophysics · Physics 2009-11-13 Hee-Jong Seo , Daniel J. Eisenstein