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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We want to establish the basic properties of a scale invariant cosmology,that also accounts for the hypothesis of scale invariance of the empty space atlarge scales. We write the basic analytical properties of the scale invariantcosmological models. The hypothesis of scale invariance of the empty space atlarge scale brings interesting simplifications in the scale invariant equationsfor cosmology. There is one new term, depending on the scale factor of thescale invariant cosmology, that opposes to gravity and favours an acceleratedexpansion. We first consider a zero-density model and find an acceleratedexpansion, going like t square. In models with matter present, thedisplacements due to the new term make a significant contribution Omega_l tothe energy-density of the Universe, satisfying an equation of the form Omega_m+ Omega_k + Omega_l = 1. Unlike the Friedman's models, there is a whole familyof flat models (k=0) with different density parameters Omega_m smaller than 1.We examine the basic relations between the density and geometrical properties,as well as the conservation laws. The models containing matter have aninflexion point, with first a braking phase followed by an acceleratedexpansion phase. The scale invariant models have interesting properties anddeserve further investigations.

Scale invariant cosmology II: model equations and properties