English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We establish a new self-consistent model of coupling between the cosmic darkenergy and dark matter in the framework of the rheological approach, which isbased on the representation of the equations of state in terms of integraloperators of the Volterra-type. We elaborate the so-called four-kernel model,in the framework of which both the dark energy and dark matter pressures arepresented by two integrals containing the energy densities of the dark energyand dark matter. For the Volterra operators, the kernels of which areassociated with the effects of fading memory, the corresponding isotropichomogeneous cosmological model is shown to be exactly integrable. We considerthe classification of the model exact solutions, based on the analysis of rootsof the characteristic polynomial associated with the key equation of thepresented model. The scalars of the pressure and energy-density of the darkenergy and dark matter, the Hubble function and acceleration parameter arepresented explicitly as the functions of the dimensionless scale factor. Thescale factor as the function of the cosmological time is found in quadraturesand is described analytically, qualitatively and numerically. Asymptoticanalysis allowed us to classify the models with respect to behavior typical forthe Big Rip, Little Rip and Pseudo Rip (de Sitter type). Two intriguing exactcosmological solutions are discussed, which describe the super-exponentialexpansion and the symmetric bounce. New solutions are presented, whichcorrespond to the quasi-periodic behavior of the state functions of the darkfluid and of the geometric characteristics of the Universe.

Self-interaction in a cosmic dark fluid: The four-kernel rheological extension of the equations of state