[ELI5] If the beginning of the universe was 13B+ years ago, how is the boundry of the universe 46.5B ly away?
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>how is the boundry of the universe 46.5B ly away?
To the best of our knowledge there is no boundary of the universe. The models are that is like the surface of a sphere so if you go far enough you end up where you start or it is infinitely large.
What has a radius of 46.6 billion light-years is the Observable universe. That is just the part of the universe where emitted light has had enough time to reach earth from the beginning of the universe.
It is larger than you might expect for a 13.8 billion lightyears universe. The explanation is that the universe is expanding. So a point that is today 46.6 billion light-years away was closer in the past. so the light emitted at the beginning of the universe has table 13.8 lightyears through space to reach us but because the space in between has expanded what emitted it is today a lot farther away,
The observable universe is only creative to our position, in another galaxy you have the same area but centered around. You can compare it to that you can only see to the horizon on earth but the horizon is in a different locations for different observers. So just like your horizons on earth is not special our observable universe is not special.
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