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We perform a detailed dynamical analysis of various cosmological scenarios in extended (varying-mass) nonlinear massive gravity. Due to the enhanced freedom in choosing the involved free functions, this cosmological paradigm allows for a…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-05 Genly Leon , Joel Saavedra , Emmanuel N. Saridakis

It is useful to study the space of all cosmological models from a dynamical systems perspective, that is, by formulating the Einstein field equations as a dynamical system using appropriately normalized variables. We will discuss various…

General Relativity and Quantum Cosmology · Physics 2016-10-17 J. Wainwright , W. C. Lim

In this paper we exploit the theory of the dynamical systems to study the dynamics of the standard cosmological model of the universe, which is known as the $\Lambda$CDM model. We assume that the matter content in our universe consists of…

General Physics · Physics 2022-09-07 Danijela Branković , Žarko Mijajlović

For the fractional action cosmological model, derived earlier by the author from the variational principle for a fractional action functional, the exact solutions are obtained. The case of a quasi - vacuum state of matter that fills the…

General Relativity and Quantum Cosmology · Physics 2013-05-29 V. K. Shchigolev

We show that the cosmological constant favours significantly the growth of voids in the universe. This dynamical effect is investigated within a newtonian approach with an extension to Friedmann-Lema\^{\i}tre model.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Roland Triay , Henri-Hugues Fliche

A regular (i.e., singularity-free) cycling cosmological model is advanced. In the model, there are only two constants: the gravitational constant (or the Planck time) and the cosmic period. The radius of the universe is a simple periodic…

General Physics · Physics 2011-12-30 Vladimir S. Mashkevich

The Hamiltonian of an evolving Universe is shown to be formally equivalent to that of a driven quantum system, whose driving follows from the temporal dependence of the spacetime metric. This analogy allows insights from the field of driven…

General Relativity and Quantum Cosmology · Physics 2021-09-07 J. P. P. Vieira

Entropic force originates in the assumption that there is a horizon for the universe. This horizon gives rise to additional terms in the equations of motion. Using dynamical system calculations, our results show that in the presence of dark…

General Relativity and Quantum Cosmology · Physics 2020-02-18 Maryam Aghaei Abchouyeh , Behrouz Mirza , Fatemeh Sadeghi

The physical nature of the presently dominating enigmatic dark energy in the expanding universe is demonstrated to be explainable as an excess of the kinetic energy with respect to its potential energy. According to traditional Friedman…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Arved Sapar

Dynamical system techniques are extremely useful to study cosmology. It turns out that in most of the cases, we deal with finite isolated fixed points corresponding to a given cosmological epoch. However, it is equally important to analyse…

General Relativity and Quantum Cosmology · Physics 2017-03-22 Mariam Bouhmadi-López , João Marto , João Morais , César M. Silva

The Friedman equation is solved for a universe contains hotdark matter and cold dark matter. In this scenario, hot-dark matter drives an accelerating universe no cold dark matter.

Astrophysics · Physics 2007-05-23 Abbas Farmany , Amin Farmany , Mohammad Mahmoodi

A major challenge of interdisciplinary description of complex system behaviour is whether real systems of higher complexity levels can be understood with at least the same degree of objective, "scientific" rigour and universality as…

General Physics · Physics 2014-05-27 Andrei P. Kirilyuk

A holistic view of the cosmological appearance and development of space is obtained by studying space as a spherically closed surface of a 4-sphere in a zero energy balance between motion and gravitation. Such an approach re-establishes…

Astrophysics · Physics 2009-11-13 Tuomo Suntola

Chaplygin's equations describing the planar motion of a rigid body in an unbounded volume of an ideal fluid involved in a circular flow around the body are considered. Hamiltonian structures, new integrable cases, and partial solutions are…

Exactly Solvable and Integrable Systems · Physics 2009-11-11 A. V. Borisov , I. S. Mamaev

It is generally argued that the present cosmological observations support the accelerating models of the universe, as driven by the cosmological constant or `dark energy'. We argue here that an alternative model of the universe is possible…

Astrophysics · Physics 2009-11-07 J. V. Narlikar , R. G. Vishwakarma , G. Burbidge

This is the third one of three papers I have presented as an application of the Basic Unit System concept, a complex mathematical unit presented in The Basic Unit System concept and The Principle of Synergy. In this case this Bus concept is…

General Physics · Physics 2007-05-23 Edgar Paternina

We apply the dynamical systems tools to study the (linear) dynamics of Friedmann-Robertson-Walker universes that are fuelled by non-linear electrodynamics. We focus, mainly, in two particular models. In the first model the cosmic evolution…

General Relativity and Quantum Cosmology · Physics 2009-05-08 Ricardo Garcia-Salcedo , Tame Gonzalez , Claudia Moreno , Israel Quiros

We investigate non-singular bounce and cyclic cosmological evolutions in a universe governed by the extended nonlinear massive gravity, in which the graviton mass is promoted to a scalar-field potential. The extra freedom of the theory can…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-05 Yi-Fu Cai , Caixia Gao , Emmanuel N. Saridakis

We study early universe cosmologies derived from a scalar-tensor action containing cosmological constant terms and massless fields. The governing equations can be written as a dynamical system which contains no past or future asymptotic…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Andrew P. Billyard , Alan A. Coley , James E. Lidsey

Effective Riemann space effect of vacuum nonlinear electrodynamics is considered in the context of theory for unified gravitation and electromagnetism. The electromagnetic four-vector potential in the scope of Born-Infeld nonlinear…

General Relativity and Quantum Cosmology · Physics 2010-06-30 Alexander A. Chernitskii
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