3rd density Earth will remain as it is, right?

[anagogy]

I think it more the case that in 3rd density, consciousness evolves to make time/space more balanced with space/time. In 3rd density there is an imbalance with the lopsided bias towards space/time which does not exist in the higher densities. Remember, space and time are the same thing ultimately - the balance is in their unity which is the evolutionary progression.

A higher density subsumes the lower, where the lower is still embedded in the higher. So you essentially have a s/t and t/s component being "controlled" for each individual s/t and t/s experience.

I have a slightly different understanding of space and time and the densities, though I respect your perspective on it. It's always interesting to me to see other individuals interpretation of these concepts.

I agree that there is a lopsided bias towards space/time in 3D. And I also agree that "time" is just another form of "space". However, the "space" that time equals is "inner-space". And its a bit like saying steam, water, and ice are all made up of h2o. While true, they still behave very differently from one another. If you'll notice, the 3 spatial dimensions we are ordinarily familiar with in the "outer-space" of the tangible "physical world" are "enfolded" within the "space" that constitutes what we call "time". The outer-space is contained within the inner-space, in other words.

The balance *IS* in their unity, as you surmise, but that balance is to be found when you take the spectrum of densities as a whole.

1st density is polarized towards space/time more so than any other density, and the time/space component of this level of consciousness is minimal. This is why it represents the grossest and most tangible manifestation of matter.

2nd density has a slight time/space component, but is still mainly polarized towards space/time.

3rd density, while having a larger time/space component than 2nd density, is also predominately biased towards space/time.

4th density has, for the most part, an equal time/space and space/time component. Being the middle density, there an equal balance between the ethereal and material components or cycles.

In 5th density it begins to lean towards time/space.

6th density is even more polarized towards time/space. Space/time manifestation at this level, while ever possible, is only needed relatively rarely.

In 7th density, it has gone full circle to completely polarized towards time/space. In this density, tangible space/time bodily complexes need not even be recycled anymore.

The 7th density, or vibrational level, while not of itself tangibly oriented towards space/time contains the lower spectrums within its vibrations, or as you say "subsumes" them. Thus, its pure time/space conscious nature is balanced by the relatively unconscious space/time nature of 1st density.

The time/space continuum contains the space/time continuum within it. And while both are illusions in the grand scheme of things, time/space is not finite like space/time is. Space/time is an extension or inversion of time/space. It could even be thought of as a "crystallized cross-section" of a portion of a time/space probability field. Space/time is the particulate manifestation of the essential time/space "wave" nature.