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We develop a new approach to building cosmological models, in which small pieces of perturbed Minkowski space are joined together at reflection-symmetric boundaries in order to form a global, dynamical space-time. Each piece of this…

General Relativity and Quantum Cosmology · Physics 2016-04-12 Viraj A. A. Sanghai , Timothy Clifton

We generalize the cosmic energy equation to the case when massive particles interact via a modified gravitational potential of the form phi(a, r), which is allowed to explicitly depend upon the cosmological time through the expansion factor…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-23 Yuri Shtanov , Varun Sahni

In a recent study Akarsu and Dereli (Gen. Relativ. Gravit. 45:1211, 2013) discussed the dynamical reduction of a higher dimensional cosmological model which is augmented by a kinematical constraint characterized by a single real parameter,…

General Relativity and Quantum Cosmology · Physics 2015-05-06 Ozgur Akarsu , Tekin Dereli , Nihan Katirci , Mikhail B. Sheftel

In this paper, we derive new asymptotic expansions for the solutions of higher order elliptic equations in the presence of small inclusions. As a byproduct, we derive a topological derivative based algorithm for the reconstruction of…

Analysis of PDEs · Mathematics 2020-01-01 Andrea Aspri , Elena Beretta , Otmar Scherzer , Monika Muszkieta

Borel summable semiclassical expansions in 1D quantum mechanics are considered. These are the Borel summable expansions of fundamental solutions and of quantities constructed with their help. An expansion, called topological,is constructed…

Quantum Physics · Physics 2008-11-26 Stefan Giller

The ability to map the cosmological expansion has developed enormously, spurred by the turning point one decade ago of the discovery of cosmic acceleration. The standard model of cosmology has shifted from a matter dominated, standard…

Astrophysics · Physics 2009-06-23 Eric V. Linder

In this work we present cosmological quantum solutions for all Bianchi Class A cosmological models obtained by means of supersymmetric quantum mechanics . We are able to write one general expression for all bosonic components occuring in…

General Relativity and Quantum Cosmology · Physics 2009-10-31 J. Socorro , E. R. Medina

Cosmological solutions of Einstein's equations for equilibrium statistical systems of particles with scalar interaction are investigated. It is shown that the scalar field can effectively change the state equation of a statistical system,…

General Relativity and Quantum Cosmology · Physics 2010-11-29 Yu. G. Ignatyev , R. F. Miftakhov

Universe structure emerges in the unreduced, complex-dynamical interaction process with the simplest initial configuration (two attracting homogeneous fields). The unreduced interaction analysis avoiding any perturbative model gives…

General Physics · Physics 2015-03-20 Andrei P. Kirilyuk

Asymptotic expansions for generalised trigonometric integrals are obtained in terms of elementary functions, which are valid for large values of the parameter $a$ and unbounded complex values of the argument. These follow from new…

Classical Analysis and ODEs · Mathematics 2025-08-11 T. M. Dunster

The current standard model of cosmology, the LambdaCDM model, is based on the homogeneous FLRW solutions of the Einstein equations to which some perturbations are added to account for the CMB features and structure formation at large…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-14 Marie-Noëlle Célérier

We construct high-precision models of the Universe that contain radiation, a cosmological constant, and periodically distributed inhomogeneous matter. The density contrasts in these models are allowed to be highly non-linear, and the…

General Relativity and Quantum Cosmology · Physics 2017-02-24 Viraj A. A. Sanghai , Timothy Clifton

We consider general curvature-invariant modifications of the Einstein-Hilbert action that become important only in regions of extremely low space-time curvature. We investigate the far future evolution of the universe in such models,…

With the era of precision cosmology upon us, and upcoming surveys expected to further improve the precision of our observations below the percent level, ensuring the accuracy of our theoretical cosmological model is of the utmost…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-30 Hayley J. Macpherson

In earlier work it was shown that a weak modification of general relativity, in the linearized approach, renders a spherically symmetric and stationary model of the Universe. This was due to the presence of a third mode of polarization in…

General Relativity and Quantum Cosmology · Physics 2015-02-11 Christian Corda

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

On the basis of the relativistic kinetic theory the relativistic statistical systems with scalar interaction particles are investigated. The self-consistent system of the equations describing self-gravitating plasma with interpartial scalar…

General Relativity and Quantum Cosmology · Physics 2013-07-10 Yu. G. Ignat'ev

We propose that complex symmetry gravitational theory (CSGT) explain the accelerating expansion of universe. In this paper universe is taken as the double complex symmetric space. Cosmological solution is obtained within CSGT. The…

Astrophysics · Physics 2009-11-13 Ying Shao , Yuan-xing Gui , Wei Wang

Cosmological perturbation theory is a powerful tool to predict the statistics of large-scale structure in the weakly non-linear regime, but even at 1-loop order it results in computationally expensive mode-coupling integrals. Here we…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-17 Xiao Fang , Jonathan A. Blazek , Joseph E. McEwen , Christopher M. Hirata

In this paper I investigate the possibility to test Einstein's equations with observations of cosmological large scale structure. I first show that we have not tested the equations in observations concerning only the homogeneous and…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-31 Ruth Durrer
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