English
Related papers

Related papers: Cosmic voids and the kinetic analysis

200 papers

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

The formation of cosmic structures is an important diagnostic for both the dynamics of the cosmological model and the underlying theory of gravity. At the linear level of these structures, certain degeneracies remain between different…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-02 Lavinia Heisenberg , Matthias Bartelmann

The $q$-theory approach to the cosmological constant problem is reconsidered. The new observation is that the effective classical $q$-theory gets modified due to the backreaction of quantum-mechanical particle production by spacetime…

High Energy Physics - Theory · Physics 2016-09-13 F. R. Klinkhamer , G. E. Volovik

The Vlasov-Einstein system describes a self-gravitating, collisionless gas within the framework of general relativity. We investigate the initial value problem in a cosmological setting with spherical, plane, or hyperbolic symmetry and…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Gerhard Rein

The linear cosmological perturbation theory of an almost homogeneous and isotropic perfect fluid universe is reconsidered and formally simplified by introducing new covariant and gauge-invariant variables with physical interpretations on…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Winfried Zimdahl

These lecture notes introduce analytical tools, methods and results describing the growth of cosmological structure beyond the linear regime. The presentation is focused on the single flow regime of the Vlasov-Poisson equation describing…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-03 Francis Bernardeau

Production of gravitational vacuum defects and their contribution to the energy density of our Universe are discussed. These topological microstructures (defects) could be produced in the result of creation of the Universe from "nothing"…

General Relativity and Quantum Cosmology · Physics 2008-01-03 V. Burdyuzha , G. Vereshkov , J. Pacheco

In these lecture notes I review the theory of the non--linear evolution of cosmological perturbations in a self--gravitating collisionless medium, with vanishing vorticity. The problem is first analyzed in the context of the Newtonian…

Astrophysics · Physics 2015-06-24 Sabino Matarrese

Cosmic voids - the low density regions in the Universe - as characteristic features of the large scale matter distribution, are known for their hyperbolic properties. The latter implies the deviation of photon beams due to their…

General Relativity and Quantum Cosmology · Physics 2020-12-03 M. Samsonyan , A. A. Kocharyan , A. Stepanian , V. G. Gurzadyan

We consider a perturbative approach to the Vlasov-Poisson system for cosmic structure formation that does not rely on any truncation of the momentum-cumulant hierarchy. The generally non-trivial linear solution is computed by solving a…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-14 Hannes Heisler , Marvin Sipp , Matthias Bartelmann

A modified-gravity theory is considered with a four-form field strength F, a variable gravitational coupling parameter G(F), and a standard matter action. This theory provides a concrete realization of the general vacuum variable q as the…

General Relativity and Quantum Cosmology · Physics 2009-11-13 F. R. Klinkhamer , G. E. Volovik

A kinetic theory of relativistic gases in a two-dimensional space is developed in order to obtain the equilibrium distribution function and the expressions for the fields of energy per particle, pressure, entropy per particle and heat…

General Relativity and Quantum Cosmology · Physics 2009-11-07 G. M. Kremer , F. P. Devecchi

The particles of a classical relativistic gas are supposed to move under the influence of a quasilinear (in the particle four-momenta), self-interacting force inbetween elastic, binary collisions. This force which is completely fixed by the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Winfried Zimdahl , Alexander B. Balakin

The Vlasov equation of kinetic theory is introduced and the Hamiltonian structure of its moments is presented. Then we focus on the geodesic evolution of the Vlasov moments. As a first step, these moment equations generalize the…

Adaptation and Self-Organizing Systems · Physics 2008-04-24 Cesare Tronci

The dynamical equations describing the evolution of a self-gravitating fluid can be rewritten in the form of a Schrodinger equation coupled to a Poisson equation determining the gravitational potential. This wave-mechanical representation…

Astrophysics · Physics 2009-11-07 Peter Coles , Kate Spencer

We apply kinetic field theory to non-linear cosmic structure formation. Kinetic field theory decomposes the cosmic density field into particles and follows their trajectories through phase space. We assume that initial particle momenta are…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-24 Sara Konrad , Matthias Bartelmann

We show that the formation of large-scale structures through gravitational instability in the expanding universe can be fully described through a path-integral formalism. We derive the action S[f] which gives the statistical weight…

Astrophysics · Physics 2009-11-10 P. Valageas

Cosmic voids are low-mass-density regions on intergalactic scales. They are where cosmic expansion and acceleration are most dominant, important places to understand and analyze for cosmology. This entry summarises theoretical underpinnings…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-01 Yan-Chuan Cai , Mark Neyrinck

The production of gravitational vacuum defects and their contribution in energy density of the Universe are discussed. These topological microstructures could be produced as the result of defect creation of the Universe from "nothing" as…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Vladimir Burdyuzha , J. A. de Freitas Pacheco , Grigory Vereshkov

We study a general relativistic particle action obtained by incorporating the Hamiltonian constraints into the formalism as a toy model for general relativity and string theory. We show how a non-vanishing cosmological constant and a…

High Energy Physics - Theory · Physics 2007-05-23 W. F. Chagas-Filho