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

Gravitationally coupled scalar fields $\phi $, distinguished by the choice ofan effective self-interaction potential $V(\phi )$, simulating a temporarilynon-vanishing cosmological term, can generate both inflation and late timeacceleration. In scalar field cosmological models the evolution of the Hubblefunction is determined, in terms of the interaction potential, by a Riccatitype equation. In the present work we investigate scalar field cosmologicalmodels that can be obtained as solutions of the Riccati evolution equation forthe Hubble function. Four exact integrability cases of the field equations arepresented, representing classes of general solutions of the Riccati evolutionequation. The solutions correspond to cosmological models in which the Hubblefunction is proportional to the scalar field potential plus a linearlydecreasing function of time, models with the time variation of the scalar fieldpotential proportional to the potential minus its square, models in which thepotential is the sum of an arbitrary function and the square of the functionintegral, and models in which the potential is the sum of an arbitrary functionand the derivative of its square root, respectively. The cosmologicalproperties of all models are investigated in detail, and it is shown that theycan describe the inflationary or the late accelerating phase in the evolutionof the Universe

A Riccati equation based approach to isotropic scalar field cosmologies