Nothing does not exist.
There is always something.
And if this something was nothing,
then nothing is something.
The nothing would be the idealized state of “something, that doesn’t exist”.
I am convinced, that we will later return to a notion of something what conformes to the aether (αἰθήρ).
The door thither are all these ‘particles without weight’ (Photon, Higgs, ..), which interact with other particles, what cannot be.
Once adopted
Let us simply assume, that time stands orthogonal on the euclidean space, and gravity stands orthogonal to this space-time.
This could solve many problems.
Every physical thing has an extension in space, time and gravity. It has a width, a height, a depth, exists from now to then, and it has a weight. A 100 meter lane extends 100 meter in space. What lasts for a year, extends a year in time. What weights 1 kilogramm, extends 1 Kg in gravity.
Width, height and depth stand orthogonal on each other. Same with both of the others. When time passes, then the entire space moves in one direction throught time, without getting changed by that. We are still able to imagine this picture quite well. This is expressed by the word ‘orthogonal’.
Space, time and gravity on their own are endless. There is no place in the universe, where they are not there.
Gravity appears to us and works on us like an attracting force. The reason is, that we can perceive the euclidean space only, but not any further. And what we can see from this perspective, is just a projection of the higher dimensional gravity, thrown at our 3-dimensional space. We only see the shadow.
We cannot inverse gravity, so that it works to the other direction as a repelling force. For this reason it is the only force that cannot be shielded. Because it’s not a force at all. It just looks this way from this perspective.
Conclusion
Projections can be quite confusing. You generally cannot conclude from a projection back to the whole. And for that, we can’t understand gravity from our perspective.
(Dedicated to my favorite mathematician Henri Poincaré)