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Related papers: Non-linear Fields in Generalized Cosmologies

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In the perturbative approach, substructures in the lens can be reduced to their effect on the two perturbative fields $f_1$ and $\frac{d f_0}{d\theta}$. A simple generic model of elliptical lens with a substructure situated near the…

Astrophysics · Physics 2009-11-13 C. Alard

Observations of redshift-space distortions in spectroscopic galaxy surveys offer an attractive method for observing the build-up of cosmological structure. In this paper we develop and test a new statistic based on anisotropies in the…

Astrophysics · Physics 2009-11-13 Will J Percival , Martin White

The abundance and distribution of collapsed objects such as galaxy clusters will become an important tool to investigate the nature of dark energy and dark matter. Number counts of very massive objects are sensitive not only to the equation…

Astrophysics · Physics 2010-05-12 L. R. Abramo , R. C. Batista , L. Liberato , R. Rosenfeld

We introduce an emulator approach to predict the non-linear matter power spectrum for broad classes of beyond-$\Lambda$CDM cosmologies, using only a suite of $\Lambda$CDM $N$-body simulations. By including a range of suitably modified…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-02 Benjamin Giblin , Matteo Cataneo , Ben Moews , Catherine Heymans

We derive a non-perturbative, closed, analytic equation for the non-linear power spectrum of cosmic density fluctuations. This result is based on our kinetic field theory (KFT) of cosmic structure formation and on evaluating particle…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-23 Matthias Bartelmann , Felix Fabis , Sara Konrad , Elena Kozlikin , Robert Lilow , Carsten Littek , Johannes Dombrowski

Linear cosmological perturbations of a large class of modified gravity and dark energy models can be unified in the effective field theory of cosmic acceleration, encompassing Horndeski scalar-tensor theories and beyond. The fully available…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-25 Lucas Lombriser , Andy Taylor

We consider the response of a multicomponent body to $n$ fields, such as electric fields, magnetic fields, temperature gradients, concentration gradients, etc., where each component, which is possibly anisotropic, may cross couple the…

Materials Science · Physics 2016-02-23 Mordehai Milgrom , Graeme W. Milton

Hamilton et al. have suggested an invaluable scaling formula which describes how the power spectra of density fluctuations evolve into the nonlinear regime of hierarchical clustering. This paper presents an extension of their method to…

Astrophysics · Physics 2016-06-08 J. A. Peacock , S. J. Dodds

Cosmologies with running cosmological term (Lambda) and gravitational Newton's coupling (G) may naturally be expected if the evolution of the universe can ultimately be derived from the first principles of Quantum Field Theory or String…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Javier Grande , Joan Sola , Julio C. Fabris , Ilya L. Shapiro

Gravitational lensing of distant objects caused by gravitational tidal forces from inhomogeneities in the universe is weak in most cases, but it is noticed that it gives a great deal of information about the universe, especially regarding…

Astrophysics · Physics 2008-11-26 Kenji Tomita , Premana Premadi , Takahiro T. Nakamura

In the era of precision cosmology, the cosmological constant $\Lambda$ gives quite an accurate description of the evolution of the Universe, but it is still plagued with the fine-tuning problem and the cosmic coincidence problem. In this…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-27 Srijita Sinha , Narayan Banerjee

Using third-order perturbation theory, we derive a relation between the mean divergence of the peculiar velocity given density and the density itself. Our calculations assume Gaussian initial conditions and are valid for Gaussian filtering…

Astrophysics · Physics 2015-06-24 Michal Chodorowski , Ewa Lokas , Agnieszka Pollo , Adi Nusser

We present a new method for calculating loops in cosmological perturbation theory. This method is based on approximating a $\Lambda$CDM-like cosmology as a finite sum of complex power-law universes. The decomposition is naturally achieved…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-25 Marko Simonović , Tobias Baldauf , Matias Zaldarriaga , John Joseph Carrasco , Juna A. Kollmeier

Major observational efforts in the coming decade are designed to probe the equation of state of dark energy. Measuring a deviation of the equation-of-state parameter w from -1 would indicate a dark energy that cannot be represented solely…

Astrophysics · Physics 2009-03-12 Alan Cooney , Simon DeDeo , Dimitrios Psaltis

We give a detailed and improved presentation of our recently proposed formalism for non-linear perturbations in cosmology, based on a covariant and fully non-perturbative approach. We work, in particular, with a covector combining the…

Astrophysics · Physics 2009-11-13 David Langlois , Filippo Vernizzi

Perturbation theory of large-scale structures of the Universe at next-to-leading order and next-to-next-to-leading order provides us with predictions of cosmological statistics at sub-percent level in the mildly non-linear regime. Its use…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-08 Ken Osato , Takahiro Nishimichi , Atsushi Taruya , Francis Bernardeau

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 compute the universal generic corrections to the power spectrum in slow-roll inflation due to unknown high-energy physics. We arrive at this result via a careful integrating out of massive fields in the "in-in" formalism yielding a…

High Energy Physics - Theory · Physics 2015-03-19 Mark G. Jackson , Koenraad Schalm

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

We develop a path-integral formalism to study the formation of large-scale structures in the universe. Starting from the equations of motion of hydrodynamics (single-stream approximation) we derive the action which describes the statistical…

Astrophysics · Physics 2009-11-11 Patrick Valageas