arXiv subjects

N. N. Fimin

Publications and source records attributed to N. N. Fimin.

8 recordsLinked to original sources

arXiv2026

The stability of voids in the Local Universe: The role of the cosmological constant

The Vlasov kinetic formalism is employed to study the evolution and stability of cosmic voids in the Local Universe, taking into account not only the gravitational attraction, but also the repulsive effect of the cosmological constant (i.e., local dark energy). In accordance with the theorem on the general function of the identity between the gravitational fields of a sphere and a point mass, the cosmological constant provides a natural explanation for the Hubble tension, attributing it to local and global flows characterized by different Hubble parameters. The crucial role of the Λ-repulsion in maintaining the stability of voids at the present epoch is demonstrated when Landau damping suppresses discrete collapse modes and prevents random local density perturbations inside the voids from growing and incorporating new galaxies into the walls. Inside the voids, the Λ-repulsion exceeds the attractive force of the residual matter, driving matter outward and accelerating its migration toward the void boundaries. In the Local (late) Universe, cosmic voids have entered a stage characterized by stable and more pronounced walls, as studied via observational surveys across different redshift ranges.

astro-ph.CO↗

arXiv2025

Cosmic voids and the kinetic analysis. V. Hubble tension, the cosmological constant and aperiodic filaments

We study the appearance and specific properties of the structures in the local Universe by means of the Vlasov kinetic technique. We consider the role of the cosmological constant in local structure formation via the theorem on the general function that satisfies the identity of the gravity of the sphere and of the point mass. Then, the Hubble tension is naturally explained as a result of two flows, a local and a global one, with non-coinciding Hubble parameters. The linearized Vlasov-Poisson equation with the cosmological term is shown to lead to van Kampen's waves, Landau damping, and then to aperiodic structures. Aperiodicity thereby emerges as a intrinsic feature of the filamentary and void structure of the local Universe, and reveals the self-consistent field mechanism of its formation. The damping of the aperiodicity is then predicted and can be observationally traced upon the increase in the scale of the filaments.

astro-ph.CO↗

arXiv2025

Cosmic voids and the kinetic analysis. IV. Hubble tension and the cosmological constant

The formation of the cosmic structures in the late Universe is considered using Vlasov kinetic approach. The crucial point is the use of the gravitational potential with repulsive term of the cosmological constant which provides a solution to the Hubble tension, that is the Hubble parameter for the late Universe has to differ from its global cosmological value. This also provides a mechanism of formation of stationary semi-periodic gravitating structures of voids and walls, so that the cosmological constant has a role of the scaling and hence can be compared with the observational data for given regions. The considered mechanism of the structure formation in late cosmological epoch then is succeeding the epoch described by the evolution of primordial density fluctuations.

gr-qc↗

arXiv2023

Cosmic voids and the kinetic analysis. III. Hubble tension and structure formation in the late Universe

We study structure formation in the late Universe within the Vlasov kinetic self-consistent field approach. Our work is principally focused on the use of the modified gravitational potential with a repulsive term of the cosmological constant, which is directly linked to observations that enable characterizations of the Hubble tension as the result of local and global flows. We formulate the criteria for the formation of the semi-periodic gravitating structures, along with the predictions of their quantitative scales associated with observable parameters. Our principal conclusion is that filament formation in the Local (late) Universe can proceed as a deterministic process that is distinct from the structures at larger scales that result from the essentially stochastic dynamics of density perturbations.

astro-ph.CO↗

arXiv2023

Cosmic voids and the kinetic analysis. II. Link to Hubble tension

We consider a principal problem, that of the possible dominating role of self-consistent gravitational interaction in the formation of cosmic structures: voids and their walls in the local Universe. It is in the context of the Hubble tension as a possible indication of the difference in the descriptions of the late (local) and early (global) Universe. The kinetic Vlasov treatment enables us to consider the evolution of gravitating structures where the fundamental role has the modified gravitational potential with a cosmological constant, leading to the prediction of a local flow with a Hubble parameter that is nonidentical to that of the global Hubble flow. The Poisson equation for a potential with an additional repulsive term, including an integral equation formulation, is analyzed, and we predict the appearance of multiply connected two-dimensional gravitating structures and voids in the local Universe. The obvious consequence of the developed mechanism is that the cosmological constant poses a natural scaling for the voids, along with the physical parameters of their local environment, which can be traced in observational surveys.

astro-ph.CO↗

arXiv2022

Cosmic voids and the kinetic analysis

The kinetic approach to the formation of the filaments in the large-scale matter distribution in the Universe is considered within the Vlasov formalism. The structures arise due to the self-consistent dynamics, along with the repulsive term in the modified Newtonian gravity which includes the cosmological constant. That modified gravity enables one to describe the Hubble tension as a result of two flows, the local and global ones. The criteria for formation of non--stationary semi-periodic structures in a system of gravitating particles described by Vlasov--Poisson equations are obtained in the case of that repulsive term. The obtained dispersion relations for the Vlasov equation in the vicinity of the singular point of the modified gravitational potential demonstrate the possibility of the emergence of filaments as coherent complex states of relative equilibrium in non--stationary systems as structures of low dimensions (walls), and voids between them, of scales (diameters) defined by the balance between the gravity and repulsive term of the cosmological constant.

astro-ph.CO↗

arXiv2022

On the origin of cosmic web

The emergence of one and two-dimensional configurations -- Zeldovich pancakes -- progenitors of the observed filaments and clusters and groups of galaxies, is predicted by means of a developed kinetic approach in analyzing the evolution of initial density perturbations. The self-consistent gravitational interaction described by Vlasov-Poisson set of equations with branching conditions is shown to predict two-dimensional structures as of layers of increased density and voids between them, i.e. the cellular macro-structure of the Universe. The modified potential of weak-field General Relativity is involved, which enables one to explain the Hubble tension, revealing the conceptual discrepancy in the local galactic flows and the cosmological expansion. This demonstrates the possible essential role of self-consistent gravity in the formation of the cosmic web.

astro-ph.CO↗

arXiv2020

The modified Newton attraction law and its connection with cosmological $Λ$--term

We consider the possibility of generalizing the Newtonian law of gravity and the transition to a general relativistic model for weak fields with the inclusion of a repulsive term identified as a cosmological constant. The analysis includes that of the test particle's motion in a modified gravitational field of the Hilbert metric and then the problem of the reverse transition from the post-Galilean case to the construction of a modified exact point mass metric which includes the $Λ$-term.

gr-qc↗