The physics inside one realm may differ extremely from the physics of another realm.
For instance, I suspect sub-atomic particles are moving so fast we can't even measure them*. Those particles can do things (like travel faster than the speed of light). They are not bound by the physical laws of our realm.
The consequences of the physics in one realm manifest into a new set of physics of a bigger realm. Our laws differ from those of subatomic particles. That progression could be endless. Our universe may be the building block (a speck of sand) to a larger realm, in which those physics differ from ours. Our neighbors (other specks of sand) are entire universes, maybe consisting of entirely different physics.
*Spectrometers use light. We don't yet understand that (Light) either. Such measurements can be flawed. I suspect the reason some particles exude duality is due to our flawed measurement techniques.