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Redshift-space clustering distortions provide one of the most powerful probes to test the gravity theory on the largest cosmological scales. We perform a systematic validation study of the state-of-the-art statistical methods currently used…

We use the cosmic shear data from the Canada-France-Hawaii Telescope Lensing Survey to place constraints on $f(R)$ and {\it Generalized Dilaton} models of modified gravity. This is highly complimentary to other probes since the constraints…

宇宙学与河外天体物理 · 物理学 2015-10-21 Joachim Harnois-Déraps , Dipak Munshi , Patrick Valageas , Ludovic van Waerbeke , Philippe Brax , Peter Coles , Luca Rizzo

In this paper, we develop a theory of redshift distortion of the galaxy power spectrum in the discrete wavelet transform (DWT) representation. Because the DWT power spectrum is dependent of both the scale and shape (configuration) of the…

天体物理学 · 物理学 2009-11-07 Xiao-Hu Yang , Long-Long Feng , Yao-Quan Chu , Li-Zhi Fang

We carry out a suite of cosmological simulations of modified action f(R) models where cosmic acceleration arises from an alteration of gravity instead of dark energy. These models introduce an extra scalar degree of freedom which enhances…

天体物理学 · 物理学 2008-12-30 Hiroaki Oyaizu , Marcos Lima , Wayne Hu

Over the past century, General Relativity (GR) has been a cornerstone of gravitational theory. However, recent cosmological observations, such as the accelerated expansion of the Universe, challenge its completeness and the standard…

广义相对论与量子宇宙学 · 物理学 2025-06-02 Lakhan V. Jaybhaye

The distribution of galaxies provides an ideal laboratory to test for deviations from General Relativity. In particular, redshift-space distortions are commonly used to constrain modifications to the Poisson equation, which governs the…

宇宙学与河外天体物理 · 物理学 2022-10-19 Sveva Castello , Nastassia Grimm , Camille Bonvin

In this work we present a brief discussion about modified and extended cosmological models using current observational tests. We show that according to these astrophysical samples based in late universe measurements, theories like $f(R)$…

广义相对论与量子宇宙学 · 物理学 2021-01-25 Celia Escamilla-Rivera

This study conducts a meticulous examination of the cosmological implications inherent in Rastall gravity and $f(R)$ gravity models, assessing their efficacy across distinct cosmic epochs, from early universe structure formation to…

广义相对论与量子宇宙学 · 物理学 2025-01-14 Muhammad Yarahmadi , Amin Salehi , Hadis Mousavi

We extract constraints on the transition redshift $z_{tr}$, determining the onset of cosmic acceleration, predicted by an effective cosmographic construction, in the framework of $f(T)$ gravity. In particular, employing cosmography we…

广义相对论与量子宇宙学 · 物理学 2015-06-19 Salvatore Capozziello , Orlando Luongo , Emmanuel N. Saridakis

The late-time acceleration of the universe remains one of the most significant open problems in modern cosmology. Modified gravity frameworks such as $f(T)$ gravity provide a geometric alternative to dark energy by attributing cosmic…

广义相对论与量子宇宙学 · 物理学 2026-05-07 Anirudh Pradhan , S. A. Salve , V. B. Raut , S. H. Shekh

We present a novel approach for reconstructing the $f(Q)$ gravitational theory using parameterizations of the deceleration parameter or alternative options. This method enables the development of modified gravity scenarios that align with…

广义相对论与量子宇宙学 · 物理学 2025-02-26 G. G. L. Nashed

A new and promising avenue was recently developed for analyzing large-scale structure data with a model-independent approach, in which the linear power spectrum shape is parametrized with a large number of freely varying wavebands rather…

宇宙学与河外天体物理 · 物理学 2024-01-24 Luca Amendola , Marco Marinucci , Massimo Pietroni , Miguel Quartin

The reconstruction scheme is developed for modified $f(R)$ gravity with realistic matter (dark matter, baryons, radiation). Two versions of such theory are constructed: the first one describes the sequence of radiation and matter…

高能物理 - 理论 · 物理学 2008-11-26 Shin'ichi Nojiri , Sergei D. Odintsov

We perform a validation of estimates of the growth rate of structure, described by the parameter combination $f\sigma_8$, in modified gravity cosmologies. We consider an analysis pipeline based on the redshift-space distortion modelling of…

宇宙学与河外天体物理 · 物理学 2016-11-08 Alexandre Barreira , Ariel G. Sánchez , Fabian Schmidt

Upcoming Large Scale Structure surveys aim to achieve an unprecedented level of precision in measuring galaxy clustering. However, accurately modeling these statistics may require theoretical templates that go beyond second-order…

宇宙学与河外天体物理 · 物理学 2023-11-21 M. Icaza-Lizaola , Yong-Seon Song , Minji Oh , Yi Zheng

Low redshift surveys of galaxy peculiar velocities provide a wealth of cosmological information. We revisit the idea of extracting this information by directly measuring the redshift-space momentum power spectrum from such surveys. We…

宇宙学与河外天体物理 · 物理学 2019-06-19 Cullan Howlett

Modern galaxy surveys focus on the galaxy power spectrum or 2-point correlation function to test and constrain cosmological models. Additional information comes from higher-order N-point functions, but their analysis is challenging. A…

宇宙学与河外天体物理 · 物理学 2021-03-17 Marcel Schmittfull , Azadeh Moradinezhad Dizgah

We elucidate the importance of the consistent treatment of gravity-model specific non-linearities when estimating the growth of cosmological structures from redshift space distortions (RSD). Within the context of standard perturbation…

宇宙学与河外天体物理 · 物理学 2017-07-26 Benjamin Bose , Kazuya Koyama , Wojciech A. Hellwing , Gong-Bo Zhao , Hans A. Winther

We take an Effective Field Theory (EFT) approach to unifying existing proposals for the origin of cosmic acceleration and its connection to cosmological observations. Building on earlier work where EFT methods were used with observations to…

宇宙学与河外天体物理 · 物理学 2013-09-24 Jolyon K. Bloomfield , Éanna É. Flanagan , Minjoon Park , Scott Watson
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