eli5: If space is expanding faster than light in all direction. Why hasn’t the space between our atoms expanded to infinite?
In: 530
It isn’t, at least not out to the horizon of what we can see. In any case, the “speed” of expansion is related to how far away you are from a point in space. If you look out one light year, space might expand (this a totally made up speed, not at all close to the actual speed that is happening) 1 meter in a second. Meaning each second you are looking at it, that point is 1 meter further away, then 1 more further again and again every second. But go out another light year past that, a total of 2 light years in a line, and there is an additional meter, that is, 1 more meter of new space in each of the two light years.
Saying that space is expanding faster than the speed of light means that more new space is created in a second than light could travel across in that second. It’s not a direct measure of how fast space is expanding, it’s a measure of how far away you have to look before light can no longer ever reach you from that point because the light will never have enough time to reach you.
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