Info about the aether or ether can be Googled. However, the basic, simple understanding is in recognizing that science has confirmed that subatomic particles are waves as well as particles.
In simple practical sense, the thing we call "nothing" or "emptiness" is the aether. The aether fills everything, but is most active wherever there is highest gravity mass. If a black hole truly is as science has calculated, black holes have great aether activity at their centers, possibly greater than anywhere else that we know about.
Again, in simple thinking, look at a wave in the ocean. A wave is made up of the chunk of water that is in it at a certain instant. As the wave moves, the wave might remain the same from instant to instant, but the water that exists in the wave is constantly changing to a new chunk of water.
The aether is like the ocean. Subatomic particles are like the waves. But aether waves are much more complex than ocean waves, and much tinier. Aether waves are produced by impingement points where rolling universes (parallel universe theory - infinite in number, each universe with a different phase vibration) impinge on each other. The slight impinging is multitudinous, and is what forms the various subatomic particles, including photons, electrons, protons, neutrons, leptons, quarks, neutrinos, etc., etc.... which roll along as the universes move "against" other universes they impinge upon.
Included in the operation is time and strings... and who knows what else. But one of the major additional things is shapes. Some shapes are 3D, but their expression shows that they might be many other dimensions higher, as well. We only see them as 3D, or maybe only 2D. (My thought is that the shapes of the more complex firings of synapses in our brains is what we can use to control aspects of the aether, mentally. Just my thought.)
Einstein's calculations were baby calculations with regard to the complexity of all this. I certainly don't know how to calculate it. But you can start by reading about aether theory, parallel universe theory, particle-wave theory, theories about time, and string theory. Unless you have an IQ in the range of Einstein or higher, you probably won't be able to combine these things enough to get the picture of what is going on.
To show you the complexity involved, consider outstretching your arm, and slowly moving your hand through the air. The thing that is really happening is that the countless numbers of subatomic particle-waves (the material of your hand) are being broken down and rebuilt by any number of parallel universes impinging on each other to form(?) aspects of our universe, that in this case are your hand moving through the air. And all of it is happening by aether activity.
At the base of it is the force of God's voice that He used to vibrate the aether He had created, into all the various "things" we recognize exist in the universe/parallel-universes/mega-universe.
The complexity of this all leaves creatures like simple human beings in awe of what is really there. This all might sound like some kind of metaphysics, but it isn't. It is the operation of the universe, all of it following laws of physics, many of which we haven't figured out, yet, and many we will never understand.