Space conservation law
In physics it is assumed that many, if not all, physical quantities are preserved. So you should also check this for the basic sizes. Space s is such a basic quantity in the mks system.
We have the conservation of mass, derived from the equivalence of mass and energy and the Conservation of energy. We also have the Weltformel, which connects the three basic quantities of the mks system space, time and mass. So now it's easy:
m = const. (in a closed system) <=> (m = const. * s according to the universal formula)
const. * s = const. <=> (/ const.)
s = const. / const. <=> (const. / const.)
s = const. (in a closed system)
Conclusion for the structure of the universe
You can see that the space is also preserved. Since we assume that the universe began at one point, the total space of the universe is always 0. Accordingly, the same number of positive and negative spaces must always have arisen in the development.
Conclusions for the structure of matter
As a counterexample for the law of space conservation, it used to be pointed out in school that when two or more atoms combine to form a molecule, they take up less space than the two atoms added together. This is due to the fact that they exchange electrons with one another and thus bond with one another. So is the correct conclusion that space is not preserved?
Relativity theory of small spaces
Ultimately, you can initially think of it as building blocks. A building block takes up so much space, if you stack one on it, it takes up twice the volume. It's a little more complicated with molecules. Two atoms joined to form a molecule take up less space than the same atoms that are free. Now you have to consider that a molecule of 2 atoms also has more mass than an atom on its own. Accordingly, after the equivalence of rotation speed and mass it rotates more. You can see that the space remains as a path. You don't even have to make the detour via the term path, but you can also imagine rotation as the stacking of spaces, if you combine the space curvature of Einstein with the Quantum Theory of Planck, namely the quantization of the room. So you can see that the space that is lost when two atoms are connected to form molecules, changes into a rotational path or also rotational space. For this rotation one would of course have to open up new dimensions of space in order to explore them geometrically. The same applies to pulsations and other movements that sweep over the same room several times.
Ultimately one can use this to create a Theory of Relativity of the small spaces and thus connect Theory of Relativity to Quantum theory via the equivalence of space and time. The theory of relativity also works on a small scale and one can speak of a space-path conservation. If space is apparently lost in a process in a closed system, it changes into path, especially in movement over the same spaces over and over again.