what is the "density" exactly means?

[unity100]

but, starting from 4th, things change. paranormal starts.

What do you mean by paranormal?
By my definition, 'paranormal' starts at 2D with the introduction of prana (or 'life force'). Science can't measure prana (or doesn't acknowledge it), so it's 'paranormal'. Maybe prana is the analog of electricity or magnetism of 1D.

Then, 3D-complexity caries with it other properties that, while possibly familiar, may be considered even more paranormal, like sentience, intentionality and thought forms.

paranormal in my definition is the point where the time/space phenomenon starts directly manifesting. life force is not paranormal, since it exists at any given point, even in 1d.

paranormal is stuff like things disappearing, or thoughts directly becoming things, telekinesis, telepathy and so on. dimensionality also starts, with different frequency entities being able to live in completely overlapping but not colliding physicalities.