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Related papers: Biased Tracers and Time Evolution

200 papers

Galaxy morphologies play an essential role in the study of the evolution of galaxies. The determination of morphologies is laborious for a large amount of data giving rise to machine learning-based approaches. Unfortunately, most of these…

Machine Learning · Computer Science 2025-10-17 Zhuo Cao , Lena Krieger , Hanno Scharr , Ira Assent

Late-time cosmology in the extended cuscuton theory is studied, in which gravity is modified while one still has no extra dynamical degrees of freedom other than two tensor modes. We present a simple example admitting analytic solutions for…

General Relativity and Quantum Cosmology · Physics 2020-07-03 Aya Iyonaga , Kazufumi Takahashi , Tsutomu Kobayashi

We present a simple heuristic model to demonstrate how feedback related to the galaxy formation process can result in a scale-dependent bias of mass versus light, even on very large scales. The model invokes the idea that galaxies form…

Astrophysics · Physics 2008-11-26 Peter Coles , Pirin Erdogdu

The systematic magnification of background sources by the weak gravitational-lensing effects of foreground matter, also called cosmic magnification, is becoming an efficient tool both for measuring cosmological parameters and for exploring…

Astrophysics · Physics 2015-06-24 Brice Menard , Takashi Hamana , Matthias Bartelmann , Naoki Yoshida

Deep redshift surveys of the universe provide the basic ingredients to compute the probability distribution function (PDF) of galaxy fluctuations and to constrain its evolution with cosmic time. When this statistic is combined with…

Astrophysics · Physics 2008-02-13 C. Marinoni , O. Le Fevre , B. Meneux , the VVDS team

Conventional approaches to cosmology inference from galaxy redshift surveys are based on n-point functions, which are under rigorous perturbative control on sufficiently large scales. Here, we present an alternative approach, which employs…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 Fabian Schmidt , Franz Elsner , Jens Jasche , Nhat Minh Nguyen , Guilhem Lavaux

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Yin-Zhe Ma , James E. Taylor , Douglas Scott

We consider an evolution operator for a discrete Langevin equation with a strongly hyperbolic classical dynamics and Gaussian noise. Using an integral representation of the evolution operator we investigate the high order corrections to the…

Chaotic Dynamics · Physics 2016-09-07 Gergely Palla , Gabor Vattay , Andre Voros

It is a well-established fact that massive cosmological objects exhibit a ``geometrical bias'' that boosts their spatial correlations with respect to the underlying mass distribution. Although this geometrical bias is a simple function of…

Astrophysics · Physics 2014-10-13 Evan Scannapieco , Robert J. Thacker

X-ray observations of galaxy clusters allow us to estimate the gas fraction, and thus the baryon fraction, and its evolution over time. This offers an additional cosmological probe as well as a probe of the gas behaviour in massive halos at…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-17 Hyeon Kim , Raphaël Wicker , Benjamin L'Huillier , Marian Douspis , Laura Salvati , Arman Shafieloo

In this paper, we investigate gravitational waves beyond the linear approximation, focusing on second-order contributions sourced by linearized waves in the transverse-traceless (TT) gauge. A general spacetime metric is constructed, and…

General Relativity and Quantum Cosmology · Physics 2025-05-06 M. A. Misyura

Gravitational weak lensing by large scale structures is view as a tool to probe the bias relation between the mass and the light distributions. It is explained how a particular statistic can be used to deproject the 2D mass distribution…

Astrophysics · Physics 2007-05-23 L. Van Waerbeke

Gravitational waves are propagating undulations in the spacetime fabric, which interact very weakly with their environment. In cosmology, gravitational-wave distortions are produced by most of the inflationary scenarios and their…

General Relativity and Quantum Cosmology · Physics 2016-03-30 Despoina Pazouli , Christos G. Tsagas

Observed angular positions and redshifts of large-scale structure tracers such as galaxies are affected by gravitational waves through volume distortion and magnification effects. Thus, a gravitational wave background can in principle be…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Donghui Jeong , Fabian Schmidt

We investigate the cosmic evolution of the linear bias in the framework of a flat FLRW spacetime. We consider metric perturbations in the Newtonian gauge, including Hubble scale effects. Making the following assumptions, (i) scale…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 S. Basilakos , J. B. Dent , S. Dutta , L. Perivolaropoulos , M. Plionis

We show that observational limits on the possible time variation of constants of Nature are significantly affected by allowing for both space and time variation. Bekenstein's generalisation of Maxwell's equations to allow for cosmological…

Astrophysics · Physics 2009-10-31 John D. Barrow , Chris O'Toole

When it comes to searches for extensions to general relativity, large efforts are being dedicated to accurate predictions for the power spectrum of density perturbations. While this observable is known to be sensitive to the gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-08 Claudio Llinares , Nuala McCullagh

Objects falling into an overdensity appear larger on its near side and smaller on its far side than other objects at the same redshift. This produces a dipolar pattern of magnification, primarily as a consequence of the Doppler effect. At…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-09 Camille Bonvin , Sambatra Andrianomena , David Bacon , Chris Clarkson , Roy Maartens , Teboho Moloi , Philip Bull

We investigate the evolution of non-linear density perturbations by taking into account the effects of deviations from spherical symmetry of a system. Starting from the standard spherical top hat model in which these effects are ignored, we…

Astrophysics · Physics 2009-10-31 S. Engineer , Nissim Kanekar , T. Padmanabhan

In this work we extend the perturbation theory for modified gravity (MG) in two main aspects. First, the construction of matter overdensities from Lagrangian displacement fields is shown to hold in a general framework, allowing us to find…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-22 Alejandro Aviles , Mario Alberto Rodriguez-Meza , Josue De-Santiago , Jorge L. Cervantes-Cota