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Message: <blockquote data-quote="Umbran" data-source="post: 5697228" data-attributes="member: 177">The answer is that we don't.  Not really.14 billion years ago, a thing that was 14 billion light years away sent out light.  We are receiving that light now.But the thing isn't sitting still for those 14 billion years.  It moved (or, you might say, space got added between us and it).  We know something about that motion, and we list what its distance from us would be now, not what it was back then.  Now, the balloon analogy has some relevance, but not as simply as jonsey put it.Imagine a balloon, not inflated.  Put two dots on the balloon, and start to inflate it.  Of course the distance between the dots increases, they appear to move, even though each one thinks it is sitting still on its spot on the balloon.Now, how does this get us to that "faster than light" thing?  Here's how:We humans generally measure distances along the surface of the balloon, and we assume it is a flat sheet that might stretch, but always remains flat.  If you measure that distance, yes, it can look like the objects are moving faster than light.  But, the balloon's surface is curved.  The real spacetime distance between the objects is measured through the balloon, kind of like you stuck a straight, thin wire through both dots.  Along this line, the distance is shorter than along the surface of the balloon, and the distance between them grows more slowly as the balloon inflates, so that they never move faster than light.</blockquote>

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