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Can anyone explain the expansion of space to me?
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this post was submitted on 02 Feb 2026
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i thought it was because the expansion doesnt actually make things move... all the space between all the things is getting bigger at the same time, making it look like things are moving... in aggregate that can look like more than speed of light
But things are actually moving.
The movement causes light emitted from those things to redshift, like the siren of an ambulance changing its pitch when it's moving away from you. And stars we can currently still see will disappear in the future, never to be seen again, as they move outside of our observable universe, accelerating faster away from us than the light they emit.
i thought distance caused red-shift.. prolly semantics.. but ... do 2 stationary objects on an expanding plane 'move'?
That's the thing. Nothing is actually moving, it just appears to be. Space itself is increasing in volume.
The best analogy isn't that everything's moving, it's that everything's shrinking.
If you and a friend are stood 2 metres apart and you suddenly both shrink, proportionately, to half your height, the distance between you is going to appear to have doubled, when in fact it's still 2 metres.
Universe expansion turns this on its head by the distance itself growing to 4 metres without either of you moving.
As to why this doesn't happen on local scales: gravity has a tendency to hold nearby things together. And closer still, atomic forces.