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Current theories about Universe dimensions and age put them - respectively - at about 90 G light-years wide and 13.8 G years old. To avoid implying that matter travelled faster than light, theories state that - sometime after 'time 0' - space wildy expanded "by itself", so that matter ended up enormously scattered in spite of having moved very little in comparison.

This - possibly as many other concepts in modern physics which work perfectly but remain un-imaginable - SEEMS to me to imply that:

1) No matter how big the Universe is, and what tools we will have available, it will never be possible to "see" anything coming from farther than 13.8 G light years (nothing travels faster than light); if this happened, the age of the Universe would be updated;

2) Looking very far away in one particular direction, we might be actually looking at ... ourselves, i.e. to the matter now composing our galaxy when it was still there, before being "shooted" where it is now by the expansion of space, and be reached by its own light !

3) The expansion of space creates/created enormous "gaps" amongst matter, where absolutely nothing is/was present, until waves of all sorts (gravitational & electromagnetic) reach and start moving through it;

4) The fact that we are now receiving light 13.5 G years old from far-away galaxies scattered in every direction, means that we now are at least 13.5 light years from the current "borders" of the universe. Provided - of course - that a "centrifugal" expansion of the Universe still makes any sense, with theories which no longer have anything in common with ... common sense.

Most of them seem very odd conclusions. Am I wrong on all the line ?

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    $\begingroup$ Hello and welcome to Stack Exchange! This is a question/answer forum. I noticed that your question contains both a numbered list and no question marks. You should consider asking one specific question, rather than asking many questions (numbered list) or no questions (no question marks). I have contributed a flag to this post accordingly, "unclear what you're asking." $\endgroup$
    – CR Drost
    Commented Jul 27, 2015 at 14:56
  • $\begingroup$ With regards to #2, see this Physics.SE post. For the rest of it, see this post, this post, and this post (the latter two being closed as dupes of the first). $\endgroup$
    – Kyle Kanos
    Commented Jul 27, 2015 at 15:14
  • $\begingroup$ 1) is correct in the sense that at every time the horizon is limited to the very same time. But you can see objects NOW further away as in your incipit (ca. 90 ly). 2) no, the light from a star cannot reach your location after the particles forming you. This is under every scenario. Perhaps these latter particles where once in contact with the source than inflated away. The only point where/when everything was shrunken together is bigbang , which we can't see. $\endgroup$
    – Alchimista
    Commented Feb 7, 2018 at 11:59
  • $\begingroup$ 3) more or less. However it is not strictly correct to say that empty region where always like that. As structure grow in size and their density increase, voids increase and less dense regions increase as well, independent of expansion. Expansion empties the voids even more. 4) is related to 1). I wanted to comment as for often is difficult to link answers on the "why" to the current punctual questions that come to the mind of us non specialists. Recently, I invested quite some time /energy on cosmology so I hope not to have made mistakes. I will be glad of being shown wrong. $\endgroup$
    – Alchimista
    Commented Feb 7, 2018 at 12:09

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