Maxwell-Boltzmann gas with nonstandard self-interactions: A novel approach to galactic dark matter

Muharlyamov

Zayats

2013

Class. Quantum Grav.

We establish a new self-consistent system of equations accounting for a nonminimal coupling of the cooperative gravitational, electromagnetic and pseudoscalar (axion) fields in a multi-component relativistic plasma. The axionic extension of the nonminimal Einstein-Maxwell-Vlasov theory is based on two consistent procedures. First, we use the Lagrange formalism to obtain nonminimal equations for the gravitational, electromagnetic and pseudoscalar fields with the additional sources generated in plasma. Second, we use the Vlasov version of the relativistic kinetic theory of the plasma, guided by the cooperative macroscopic electromagnetic, gravitational and axionic fields, to describe adequately the response of the plasma on the variations of these fields. In order to show the self-consistency of this approach we check directly the compatibility conditions for the master equations for the cooperative fields. Using these compatibility conditions we reconstruct the ponderomotive force, which acts on the plasma particles, and discuss the necessary conditions for existence of the distribution function of the equilibrium type.

Section: What Does the Nonminimal Coupling Scheme Add To The Model?mentioning

confidence: 99%

Nonminimal Einstein–Maxwell–Vlasov-axion model

Muharlyamov

Zayats

2013

Class. Quantum Grav.

“…Then the key equation of the second order (17) with the source term (19) can be rewritten as a pair of dynamic equations of the first order:…”

Section: A Dynamic System Associated With the Key Equationmentioning

confidence: 99%

“…Here Π(1) denotes the initial value for the DE pressure (let us remind that Π(x=1) = Π[a(t=t 0 )]). When we deal with massless particles, the corresponding source term coincides with (19), if…”

Section: Key Equation Of the Toy Modelmentioning

confidence: 99%

“…In the first part of the work [13] we introduced the so-called Archimedean-type force, which is linear in the four-gradient of the DE pressure and acts on the DM particles. This force is a relativistic generalization of the classical Archimedean force and belongs to the class of effective forces described in [14]- [19]. From mathematical point of view the presented model gives us a new self-consistent nonlinear scheme of interaction between two constituents of the cosmic medium.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Archimedean-type force in a cosmic dark fluid. II. Qualitative and numerical study of a multistage universe expansion

Bochkarev

2011

Phys. Rev. D

In this (second) part of the work we present the results of numerical and qualitative analysis, based on a new model of the Archimedean-type interaction between dark matter and dark energy. The Archimedean-type force is linear in the four-gradient of the dark energy pressure and plays a role of self-regulator of the energy redistribution in a cosmic dark fluid. Because of the Archimedeantype interaction the cosmological evolution is shown to have a multistage character. Depending on the choice of the values of the model guiding parameters, the Universe's expansion is shown to be perpetually accelerated, periodic or quasiperiodic with finite number of deceleration/acceleration epochs. We distinguished the models, which can be definitely characterized by the inflation in the early Universe, by the late-time accelerated expansion and nonsingular behavior in intermediate epochs, and classified them with respect to a number of transition points. Transition points appear, when the acceleration parameter changes the sign, providing the natural partition of the Universe's history into epochs of accelerated and decelerated expansion. The strategy and results of numerical calculations are advocated by the qualitative analysis of the instantaneous phase portraits of the dynamic system associated with the key equation for the dark energy pressure evolution.

“…We discussed the structure and properties of various effective forces, which appeared in the cosmological contexts, in the papers [23][24][25][26][27][28], the relativistic generalizations of the Stokes force, Langevin force, antifriction and tidal forces being investigated in detail. Concerning the force acting on the DM particles from the DE we would like to introduce the so-called Archimedean-type force.…”

Section: Introductionmentioning

confidence: 99%

Archimedean-type force in a cosmic dark fluid. I. Exact solutions for the late-time accelerated expansion

Bochkarev

2011

Phys. Rev. D

We establish a new self-consistent model in order to explain from a unified viewpoint two key features of the cosmological evolution: the inflation in the early Universe and the late-time accelerated expansion. The key element of this new model is the Archimedean-type coupling of the dark matter with dark energy, which form the so-called cosmic dark fluid. We suppose that dark matter particles immersed into the dark energy reservoir are affected by the force proportional to the four-gradient of the dark energy pressure. The Archimedean-type coupling is shown to play a role of effective energy-momentum redistributor between the dark matter and the dark energy components of the dark fluid, thus providing the Universe evolution to be a quasiperiodic and/or multistage process. In the first part of the work we discuss a theoretical base and new exact solutions of the model master equations. Special attention is focused on the exact solutions, for which the scale factor is presented by the anti-Gaussian function: these solutions describe the late-time acceleration and are characterized by a nonsingular behavior in the early Universe. The second part contains qualitative and numerical analysis of the master equations; we focus there on the solutions describing a multi-inflationary Universe.