First, it’s even now achievable the universe is finite. All we know for confident (typically for confident) is that it’s even larger than we can observe, effectively mainly because the farthest edges of the universe we can see do not glance like edges. The observable universe is even now large, but it has boundaries. That’s mainly because we know the universe isn’t infinitely previous — we know the Big Bang transpired some 13.8 billion a long time in the past.
That means that gentle has experienced “only” 13.8 billion a long time to journey. That’s a good deal of time, but the universe is significant adequate that scientists are really confident that there is place outside the house our observable bubble, and that the universe just isn’t previous adequate nevertheless for that gentle to have arrived at us.
(In a pleasurable twist, the universe has expanded considering that the Big Bang, so the objects that we see emitting gentle 13.8 billion a long time in the past are now some 46 billion gentle-a long time away.)
A handful of generations of telescopes — COBE, WMAP, and Planck — sought to understand the form of the universe. Was it curved like a ball, or flat like a piece of paper? If it were curved, and if we could evaluate the curve, we could get the job done out the dimension of the universe.
But all 3 telescopes say the universe is flat, which tells us absolutely nothing about the dimension of the universe.