Also, to expand on that (I have no knowledge, just making assumptions), the space between galaxies would need to either create new matter, or the matter would g

Also, to expand on that (I have no knowledge, just making assumptions), the space between galaxies would need to either create new matter, or the matter would get infinitely spread out over time? So, if the stretching thing is true, would there be areas with absolutely no matter or anything at all?