In a three dimensional world, the fundamental elements of that world all have three dimensions.
A physical world is not just a matter of length, breadth & height.
All matter is a form of energy and the fundamental properties of all energy forms are frequency, wavelength & vibration.
The three energy dimensions of all matter forms in motion are spin, orbit & rotation.
It is the spin, orbit & rotation of electrons, neutrons & protons in an atom that determine the material form of particular matter.
It is the spin, orbit & rotation of planets, moons & suns that determine the material form of a solar system.
It is the spin, orbit & rotation of different stars in a galaxy that determine that galactic system.
The spin, orbit & rotation of any form of atomic matter is measured as the energetic force, magnitude & potential of its electro-magnetic-gravity.
The Law of Attraction determines that all elemental systems with like spin, orbit & rotation are drawn unto themselves.
This is a fundamental principal of all three dimensional physical worlds.