eli5: If space is expanding faster than light in all direction. Why hasn’t the space between our atoms expanded to infinite?
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The “force” (such as it were) from space expanding is currently weaker than the electromagnetic force holding your atoms and molecules together. As the space between them expands, the molecules simply pull themselves back together through the expanding space, sort of like swimming upstream against a current.
A sort of conceptual example in the opposite direction is our experience with gravity here on earth.
The curvature of spacetime is like space itself is trying to “shrink” in the direction of the center of the earth. But the stronger force of electromagnetic repulsion between the atoms in your body and the atoms in the ground means the ground can successfully hold you up as space “flows” inward towards the center of the earth.
These are both gross oversimplifications because space isn’t “flowing” and it’s not a “force,” but good enough for an ELI5.
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