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’s gonna. You’re too early though, it takes a long time see you in about 13 billion years
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.
We are on the verge of trying to find out what the force is that holds all of our atoms together in us and all of plants and animals and everything. Some theorize that it is going to be dark matter that solves all these riddles. We need more of them scientists. You youngins need to get your ass to university.
We’ve been told for decades nothing is faster than light. So it’s not expanding faster than light
The way my physics professor explained it to me in college was that the universe expanding means that spacetime is expanding. You and everything around you are also getting bigger, but since everything is getting bigger, you can’t tell.
Look at Mr. In A Hurry, gotta have infinite expansion right now, can’t wait for it to happen at its own pace and time!
The expansion of the universe is currently too weak to affect matter that is bound by the weak, strong and EM forces. It’s also true for matter bound by gravity on the scale of a galaxy or galaxy cluster. This expansion force is quantified by Dark Energy, and its way of working is mostly unknown.
As time goes on and more space is created, dark energy may become significant for smaller and smaller groups of gravity bound matter (i.e galaxies, then star systems, then planets). It’s unknown where this stops and if matter bound by the other forces will ever be affected.
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