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 introduce a scenario in which the breakdown of conformal symmetry isresponsible for the acceleration of universe in the matter dominant era. Inthis regard, we consider a self interacting scalar field non-minimally coupledto the Ricci scalar and the trace of energy-momentum tensor. For a tracelessenergy-momentum tensor in radiation dominant era, the coupling to mattervanishes and we are left with a conformal invariant gravitational action ofDeser, where the universe may experience a decelerating phase in agreement withobservations. In matter dominant era, the coupling to matter no longervanishes, the conformal symmetry is broken down, and the matter inevitablybecomes pressureless. The corresponding field equations are obtained and it isshown that the universe may have an accelerating phase in this era, providedthat the value of self interaction coupling constant satisfies an specificlower bound. Moreover, we provide a reasonable solution to the coincidenceproblem.

Acceleration of the universe in matter dominant era by conformal symmetry breaking