The purpose of this study is to entrench the Copernican principle into cosmology with regard to dark energy (DE). A dual-universe solution is proposed for both the scale and coincidence problems of DE which is simple and involves no `fine-tuning'. It is also, in principle, testable and falsifiable. The model enables computation of the total entropy of the universe contained within the horizon expressed holographically projected onto the area of the cosmic horizon in units of Planck area. We subsequently compute the Planck entropy, which takes an irreducibly simple form. A derivation of the relation $[{DE}]={sqrt{m_{pl}.H_0}}$ is provided and we further show that this relation is valid in all (local i.e. $H'_{tau}=H'_0$) observer frames. We prove that the vacuum energy is exactly zero in this dual universe model. Lastly we propose that our analysis implies that the MOND paradigm is due to gravitation interaction of the two universes and we compute the MOND acceleration scale $a_0$ and scale invariant ${cal.{A}}_0$ as a consequence of cosmology, completely independent of galaxy dynamics. Significantly, this allows us to bring the MOND paradigm into a cosmological model without modifying General Relativity.