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Late time cosmic acceleration may be achieved by modifying gravity on large scales. This should also have consequences on the evolution of perturbations. We thus extend our study of exponential infrared $f(T)$ teleparallel gravity to…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Mahmoud Hashim , Amr A. El-Zant , Waleed El Hanafy , Alexey Golovnev

Analyses of cosmic shear typically condense weak lensing information over a range of scales to a single cosmological parameter, $S_8$. This paper presents a method to extract more information from Stage-IV cosmic shear measurements by…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-30 Calvin Preston , Alexandra Amon , George Efstathiou

We present a new numerical scheme to treat the non-linear evolution of cosmological power spectra. Governing equations for matter power spectra have been previously derived by a non-perturbative technique with closure approximation.…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-30 Takashi Hiramatsu , Atsushi Taruya

Over the last few years much attention has been given to the study of modified gravity theories in order to find a more natural explanation for the late time acceleration of the Universe. Nevertheless, a comparison of the matter power…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Amare Abebe , Alvaro de la Cruz Dombriz , Peter K. S. Dunsby

Modern datasets have the precision necessary to uncover new information by including higher-order, non-Gaussian information into cosmological inference. The marked power spectrum offers access to such information while preserving the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-05 Haruki Ebina , Martin White , Edmond Chaussidon

Standard cosmological data analyses typically constrain simple phenomenological dark-energy parameters, for example the present-day value of the equation of state parameter, $w_0$, and its variation with scale factor, $w_a$. However,…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-30 Yuewei Wen , Eva Nesbit , Dragan Huterer , Scott Watson

f(R) gravity is one of the simplest viable modifications to General Relativity: it passes local astrophysical tests, predicts both the early-time cosmic inflation and the late-time cosmic acceleration, and also describes dark matter. In…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-22 Didam Duniya , Amare Abebe , Alvaro de la Cruz-Dombriz , Peter Dunsby

We construct new classes of modified theories in which the matter sector couples with the Einstein tensor, namely we consider direct couplings of the latter to the energy-momentum tensor, and to the derivatives of its trace. We extract the…

General Relativity and Quantum Cosmology · Physics 2023-05-17 Petros Asimakis , Spyros Basilakos , Andreas Lymperis , Maria Petronikolou , Emmanuel N. Saridakis

Marked power spectra provide a computationally efficient way to extract non-Gaussian information from the matter density field using the usual analysis tools developed for the power spectrum without the need for explicit calculation of…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-02 Jessica A. Cowell , David Alonso , Jia Liu

In order to explain cosmic acceleration without invoking "dark" physics, we consider $f(R)$ modified gravity models, which replace the standard Einstein-Hilbert action in General Relativity with a higher derivative theory. We use data from…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-08 Jason Dossett , Bin Hu , David Parkinson

Uncertainties in predicting the nonlinear clustering of matter are among the most serious theoretical systematics facing the upcoming wide-field weak gravitational lensing surveys. We estimate the accuracy with which the matter power…

Astrophysics · Physics 2011-05-12 Dragan Huterer , Masahiro Takada

At linear order in cosmological perturbations, departures from the growth in the cosmological standard model can be quantified in terms of two functions of redshift $z$ and Fourier number $k$. Previous studies have performed principal…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Alireza Hojjati , Levon Pogosian , Alessandra Silvestri , Gong-Bo Zhao

We consider a model of modified gravity based on the spectral action functional, for a cosmic topology given by a spherical space form, and the associated slow-roll inflation scenario. We consider then the coupling of gravity to matter…

Mathematical Physics · Physics 2014-08-20 Branimir Cacic , Matilde Marcolli , Kevin Teh

The spatial curvature ($\Omega_K$) of the Universe is one of the most fundamental quantities that could give a link to the early universe physics. In this paper we develop an approximate method to compute the nonlinear matter power…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-19 Ryo Terasawa , Ryuichi Takahashi , Takahiro Nishimichi , Masahiro Takada

We present a new compilation of inferences of the linear 3D matter power spectrum at redshift $z\,{=}\,0$ from a variety of probes spanning several orders of magnitude in physical scale and in cosmic history. We develop a new lower-noise…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-09 Solène Chabanier , Marius Millea , Nathalie Palanque-Delabrouille

Quantum mechanical transition amplitudes directly tells the probability of each transition and which one is more favourable. Path-integrals offers a systematic methodology to compute this quantum mechanical process in a consistent manner.…

General Relativity and Quantum Cosmology · Physics 2019-12-17 Gaurav Narain , Hai-Qing Zhang

We provide a cosmological test of modified gravity with two tensorial degrees of freedom and no extra propagating scalar mode. The theory of gravity we consider admits a cosmological model that is indistinguishable from the $\Lambda$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-01 Takashi Hiramatsu , Tsutomu Kobayashi

The linear matter power spectrum is an essential ingredient in all theoretical models for interpreting large-scale-structure observables. Although Boltzmann codes such as CLASS or CAMB are very efficient at computing the linear spectrum,…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-20 Giovanni Aricò , Raul E. Angulo , Matteo Zennaro

The use of Eulerian 'standard perturbation theory' to describe mass assembly in the early universe has traditionally been limited to modes with k $\lesssim$ 0.1 h/Mpc at z = 0. At larger k the SPT power spectrum deviates from measurements…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-28 Lucía Fonseca de la Bella , Donough Regan , David Seery , Shaun Hotchkiss

We investigate the cosmological implications of modified gravities induced by the quantum fluctuations of the gravitational metric. If the metric can be decomposed as the sum of the classical and of a fluctuating part, of quantum origin,…

General Relativity and Quantum Cosmology · Physics 2016-08-02 Xing Liu , Tiberiu Harko , Shi-Dong Liang
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