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Related papers: Cosmological perturbation theory using generalized…

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Interacting dark sector (IDS) models provide a commonly explored extension of the standard $\Lambda$CDM cosmology, allowing for non-gravitational energy--momentum exchange between cold dark matter (CDM) and dark energy (DE). Although such…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-16 Matheus Wolney , Gabriel Sampaio , Humberto Borges , Iuri Baranov , Rodrigo von Marttens

We derive a minimal basis of kernels furnishing the perturbative expansion of the density contrast and velocity divergence in powers of the initial density field that is applicable to cosmological models with arbitrary expansion history,…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-14 Michael Hartmeier , Mathias Garny

We develop a framework to compute the redshift space power spectrum (PS), with kernels beyond Einstein-de Sitter (EdS), that can be applied to a wide variety of generalized cosmologies. We build upon a formalism that was recently employed…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-16 Alejandro Aviles , Georgios Valogiannis , Mario A. Rodriguez-Meza , Jorge L. Cervantes-Cota , Baojiu Li , Rachel Bean

We investigate the evolution of cosmological perturbations in models of dark energy described by a time-like unit normalized vector field specified by a general function $\mathcal{F}(\mathcal{K})$, so-called Generalized Einstein-Aether…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Richard A. Battye , Francesco Pace , Damien Trinh

Under the standard perturbation theory (SPT), we obtain the fully consistent third-order density fluctuation and kernels for the general dark energy models without using the Einstein-de Sitter (EdS) universe assumption for the first time.…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-07 Seokcheon Lee , Changbom Park , Sang Gyu Biern

We consider a new variant of cosmological perturbation theory that has been designed specifically to include non-linear density contrasts on scales 100 Mpc, while still allowing for linear fluctuations on larger scales. This theory is used…

General Relativity and Quantum Cosmology · Physics 2019-04-08 Christopher S. Gallagher , Timothy Clifton

The perturbative approach to structure formation has recently received a lot of attention in the literature. In such setups the final predictions for observables like the power spectrum is often derived under additional approximations such…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Matteo Fasiello , Zvonimir Vlah

Loop corrections to the power spectrum are frequently computed using approximate non-linear kernels adopted from an Einstein de-Sitter (EdS) cosmology. We present an algorithm that allows us to take the full time- and scale-dependence of…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-04 Mathias Garny , Petter Taule

Parameterized frameworks for modified gravity are potentially useful tools for model-independent tests of General Relativity on cosmological scales. The toy model of an Einstein-de Sitter (EdS) universe provides a safe testbed in which to…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Tessa Baker

We reformulate the averaged Einstein equations in a form suitable for use with Newtonian gauge linear perturbation theory and track the size of the modifications to standard Robertson-Walker evolution on the largest scales as a function of…

Astrophysics · Physics 2008-11-26 Juliane Behrend , Iain A. Brown , Georg Robbers

We present a novel approach, based entirely on the gravitational potential, for studying the evolution of non-linear cosmological matter perturbations. Starting from the perturbed Einstein equations, we integrate out the non-relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Ram Brustein , Antonio Riotto

(abridged)Cosmological observational programs often compare their data not only with $\Lambda$CDM, but also with extensions applying dynamical models of dark energy (DDE), with a time-dependent equation of state (EoS) parameter $w$. We…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-13 Horst Foidl , Tanja Rindler-Daller

We study the effect of the Einstein - de Sitter (EdS) approximation on the one-loop power spectrum of galaxies in redshift space in the Effective Field Theory of Large-Scale Structure. The dark matter density perturbations and velocity…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-22 Yaniv Donath , Leonardo Senatore

Many recent studies have highlighted certain failures of the standard Eulerian-space cosmological perturbation theory (SPT). Its problems include (1) not capturing large-scale bulk flows [leading to an O(1) error in the 1-loop SPT…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Matthew McQuinn , Martin White

Using a diagrammatic approach to Eulerian perturbation theory, we analytically calculate the variance and skewness of the density and velocity divergence induced by gravitational evolution from Gaussian initial conditions, including…

Astrophysics · Physics 2011-09-30 Roman Scoccimarro , Joshua Frieman

In this paper we present four simple expressions for the relativistic first and second order fractional density perturbations for $\Lambda$CDM cosmologies in different gauges: the Poisson, uniform curvature, total matter and synchronous…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Claes Uggla , John Wainwright

Reconstructions of the primordial power spectrum (PPS) of curvature perturbations from cosmic microwave background anisotropies and large-scale structure data suggest that the usually assumed power-law PPS has localised features (up to…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-16 Amel Durakovic , Paul Hunt , Subodh P. Patil , Subir Sarkar

We present a simple and intuitive approximation for solving perturbation theory (PT) of small cosmic fluctuations. We consider only the spherically symmetric or monopole contribution to the PT integrals, which yields the exact result for…

Astrophysics · Physics 2009-10-30 P. Fosalba , E. Gaztanaga

We present a local-to-global cosmological framework in which cosmic acceleration emerges from structure formation in an inhomogeneous Einstein-de Sitter (iEdS) universe, without dark energy. The model exhibits a quasilinear coasting…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-29 Peter Raffai , Dominika E. R. Kis , Dávid A. Ködmön , Adrienn Pataki , Rebeka L. Böttger , Gergely Dálya

Based on the Effective Field Theory (EFT) of cosmological perturbations, we explicitly clarify the pathology in nonsingular cubic Galileon models and show how to cure it in EFT with new insights into this issue. With the least set of EFT…

General Relativity and Quantum Cosmology · Physics 2017-06-13 Yong Cai , Hai-Guang Li , Taotao Qiu , Yun-Song Piao
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