I've been insisting this for years:

it eradicates the bullshit of hyperinflation being required to smooth the CMB,

it explains why gravity's sooo weak, compared with the contained-within-this-3d-space forces, like electromagnitism,

it explains why there exist galaxies of dark-matter which don't have any conventional-matter,

it explains why there exist galaxies of conventional-matter which don't have any dark-matter.

The gravity's diffusing through MANY 3D-spaces, not just ours.

the other forces are contained-within-this-3D-space.

Therefore OUR gravity is "dark matter" in other 3D-spaces, too.

The smoothing-of-the-CMB is simple: instead of 1x 3D-space having hyperinflation, there are thousands of 3D-spaces ( or zillions: whatever the math says matches ), & EACH of them inflated at speed-of-light or less, not at zillions-of-times-c.

The painting-method called "glazing" is essentially the same idea:

da Vince used many many thin layers of paint, to make ultra-smooth tones..

the many-many-many-3D-spaces all "underlying" each-other smoothes-out the gravity among them all, so local-lumpiness simply isn't a significant part of the equation, as it would appear.

Part of this is on the E = speed-of-gravity * mass * speed-of-light, though, so it's arithmetically identical to the conventional E=mc^2 rendition,

but would gravity & light both be traveling at the same mps speed through say a 100km of quartz?

XOR would the refractive-index be different for gravity & light?

That structural difference is what the speed-of-gravity * mass * speed-of-light variant was trying to show.

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