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There was a recent article on bbc.com for laypeople like me titled "The mystery of how big our Universe really is", which prompted me to post the following question in their comments section of Facebook, which so far has received no answer, so I am reposting it here in the hope of a better result:

"I have a simple question, which probably has an equally simple answer: if "the furthest visible regions of the Universe are estimated to be around 46 billion light years away" but at the same time "the Universe burst into existence an estimated 13.8 billion years ago", wouldn't the photons (or whatever) that we observe coming from those distant objects have had to have begun their travel towards us long before the universe existed?"

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I believe that the expansion of the universe is believed to be caused by additional space appearing at great intervals, thus expanding the amount of space which is in the universe.

So the farthest and oldest galaxies known were over thirteen billion light years away over thirteen billion years ago, but more space has kept appearing between them and Earth over billions of years, so that it is calculated that at the rate of expansion of the universe they are now about 46 billion light eyars from Earth.

You will note that 13or 14 billion light years plus another 13 or 14 billion light years, equals 26 to 28 billion light years, and that the farthest known galaxies are now about another 18 or 20 billion light years beyond that.

If nothing can travel faster than light how cul those disant galaxies receed receed a greater distance than light could travel in those billions of years?

Because our galaxy and those distant galaxies are not moving that fast. Instead space is increasing between distant parts of the universe while galaxies almost stand still.

At least that is my understanding. And it sounds a lot like some goofy theory in a science fiction movie or story to me, but apparently it is the accepted cosmological theory.

And probably a professional astronomer or physicist could give a much better explanation, but it would probably still seem very weird to most people.

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    $\begingroup$ To quote your post: "the farthest and oldest galaxies known were over thirteen billion light years away over thirteen billion years ago"- I don't believe this statement is correct. They were much closer at the time of emission, since their light also had to cross expanding space to get to us. See the note here; en.wikipedia.org/wiki/GN-z11 $\endgroup$
    – Connor Garcia
    May 24 at 17:24
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No conflict. The universe is expanding. The furthest/oldest object we can see emitted its photons approximately 13.4 billion years ago, but the universe has expanded since then and that object is now around 32 billion light-years away. See this answer or search the astronomy stack exchange for "age of universe expansion".

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