Albert Einstein pontificated the relationships of space and time. Within the Theory of Relativity, which he drafted in the Zurich patent office, he defined these relationships and the influence of speed of motion upon time itself. From his math we finally began to accept that, as objects progress toward the speed of light their time slows. Time elsewhere remains constant. He saw that, given this warpage of time, it would be impossible to exceed the speed of light (299,792,458 meters/second). This is a seemingly impossible reality to comprehend.
He further declared that the speed of light was a constant, independent of the position or speed of the observer. Many, including Einstein, thought that there must be an influence to maintain the speed of light in space.
Beyond the speed of light, relative to our position of observation, there may be universes, moving toward, away, and through us completely unnoticed. Perhaps the thing that defines one universe from another, forever dividing the entirety of all of matter and energy is a simple thing, relative motion.
If this is so, there may be many universes, each as real as the others, each occupying the same space and time for a moment, each with the same quirks of distortion within the relative movement of elements within its whole. We would see little or nothing of them but, perhaps the background noise of their interplay that seeps into our realm.
We know that the majority of mass and energy is “black” unseen and unknown to man, still, from gravitational computation, we know that it is there, somewhere. Perhaps that “black matter” is only another universe passing through us while we sleep separated from us only by its relative motion.