Einstein’s theory of general relativity describes the gravitational field around massive objects ( like Earth) as a curvature in the spacetime. But it leaves the following question unanswered; why is the spacetime curved by a mass? Through a theory that has been introduced recently, regarding a medium for a light propagation, a simple answer is introduced. It depends on redefining the rest energy for a massive object ( like a planet) as new form of kinetic energy. For a static and spherically symmetric object, with a specific radius(

In this paper, we investigate the ontological hypothesis, which implies that the spacetime is not the ultimate structure in our universe, and its existence emerges from a deeper physical entity. By using a very simple approach based on a classical problem, regarding the propagation of electromagnetic waves in empty vacuum. We were able to deduce that this deeper entity is just an omnipresent multi-rest states physical structure; aether. After that, we try to see how this aether fits in the universe that we exist in. The outcome is that its existence causes the emergence of some basic phenomena that our universe is built on. At the microscopic scale it turned out to be a source of the essential quantum phenomenon, which is currently known as the wave – particle duality. On the other hand, at the macroscopic scale it causes the emergence of spacetime curvature, around huge, massive objects like Earth, and finally, we try to visualize the prospects of aether, and how it can be a promising alternative for the dark matter.