When man fell, we fell from the realm of light to the realm of matter. But though we’re in the realm of matter, we’re still light, and we always move at light’s speed.
In its pure form—in the realm from which we fell, which is heaven—light is timeless and has no speed. It is matter that gives light speed. The denser the matter, the faster the speed.
But the speed of light must always remain constant! So what changes? The speed of time.
Falling from heaven is akin to falling from the surface of a sphere to its center; it’s akin to falling underwater, only while we’re incarnate, it’s matter in which we are “submerged.”
But light does not want to remain submerged in matter. Ever since the fall, we’ve been swimming toward the surface. In a sense, we’ve been “falling up,” or ascending. In physics terms: this is not an inertial field.
The ascension is a movement from high density to low density. We might think of matter as energy that’s very dense. The denser the matter, the faster light’s speed.
But remember: light’s speed is constant. We cannot say “the faster light’s speed;” instead we must say “the slower the speed of time.”
At the center of the sphere, c is very fast, so time is slow. And at its outermost ring, c is very slow, so time is fast. As light, we are moving from fast to slow as the universe accelerates and time slows down.
Again: the universe is accelerating (expanding). It is this ascension—which is both perpetual and universal—that creates the impression of gravity.
Einstein predicted that gravity could be “fake”—i.e. an impression created by acceleration—and this idea is discussed very succinctly in a PBS video here.