when 3rd Density deactivates

[Philosoraptor]

so all the artifacts of 3d will disappear?

all the stuff we made? the buildings, skyscrapers, xboxes, 3TB hard drives, fridges, stainless steel knives etc. Just vanish?

This is a good question. I would ask you, first of all, what makes up 3rd density?

3rd density is made up of the planet's 3rd-density collective vibratory complex of mind/body/spirits, this by extension includes all the time/space or inner plane 3rd-density thought-forms of these entities as well as the "materialized" 3rd-density creations that these entities have built out of 1st and 2nd-density materials (minerals and plants/animals).

Upon the cessation of 3rd-density activity, just as yellow-ray physical bodies decay/disintegrate over time, so too would skyscrapers, fridges and xboxes.

However! Let's not forget the planet's 4th-density entities may yet find viability in some of these artifacts and buildings, which would then be "inherited" from 3rd density and "upgraded" over time to suit 4th-density needs, thus becoming 4th-density creations.