I Is the Universe bigger than we think?

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The discussion centers on the possibility that the universe may be larger than currently understood due to the limitations of our detection capabilities, particularly the effects of inflation and the speed of light. Participants clarify that while the universe appears infinite, our ability to observe it is constrained by time and the nature of light, with the universe expanding in all directions. It is noted that accelerated inflation creates an event horizon that limits our view of certain regions of space. The consensus is that the age of the universe is determined through observations of distant galaxies moving away from us, rather than the distance we can see. Overall, the conversation emphasizes the complexities of modern cosmology and the need for further understanding of these concepts.
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Im a novice and I love reading all the great info here but I have a question. We think we know the age of the universe because thats as far as we can "see." Is it possible with inflation that the universe is actually bigger than we can detect and we are limiting the size based on our limited observational abilities?
As inflation happens, effectively, faster than the speed of light (between any given two points) and we can only see 14 billion years back, is it possible the data we need, to judge the age of the universe, is actually beyond our detection abilities. Could the age of the universe be greater because what we are seeing is just the limitations placed on our detecting abilities by space time? Could the "rest" of the universe have expanded beyond our ability to detect it, and the data never get to us because space time, between us and it, is expanding so rapidly that the radio waves, gama rays, light etc is actually getting farther away even though it is coming at us?
 
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Trailblzn said:
Is the Universe bigger than we think?
It would be REALLY REALLY hard for that to be the case since the current consensus (not an established fact) is that the universe is infinite in extent. You can't GET bigger than that.

You fundamentally misunderstand modern cosmology. I encourage you to do some basic reading and you will quickly correct your misunderstanding.

The part of the universe that we can't see with light is the 400,000 years or so prior to the Surface of Last Scattering and the belief is that we are likely to be able, someday, to see further back than that with other technologies than are presently available.
 
Thank you for your reply, I genuinely appreciate it. Can you elaborate on which part of my question fundamentally misunderstands modern cosmology? The link http://preposterousuniverse.com/writings/cosmologyprimer/index.html is broken, just an FYI. I understand (or think I understand) the balloon analogy. What I think is correct, the universe is expanding in all directions, it is expanding faster the farther it is away from us. It is or can be expanding faster than the speed of light so the stuff at the edges of the universe may be expanding faster than any thing can travel to us. Is this the part that I misunderstand? Do you have any other suggested materials for me to read? I really appreciate your assistance.
 
Trailblzn said:
We think we know the age of the universe because that's as far as we can "see."
How far we can 'see' has nothing to do with it. We know the age because everything is moving away from us at a rate proportional to its distance from us, so simple extrapolation backwards gives us a time when it was all together. That works no matter how large or limited our sight distance is. Sight distance seems to be limited by speed of light. If it was twice as fast, we could see twice as far.

The infinite size consensus comes from the fact that it seems to look identical everywhere and not different this way than in some other direction. Hence it is reasonable to conclude that it looks similarly isotropic and homogeneous to the observers in those other places as well, in which case there is no edge (a place where there is more stuff on one side than the other).

As inflation happens, effectively, faster than the speed of light (between any given two points) and we can only see 14 billion years back
Inflation doesn't directly limit our sight distance. Time does, since (as phinds points out) the universe wasn't transparent at first, so we can only see back as far in time as when it was.
Inertial inflation doesn't limit sight distance, but accelerated inflation does since it forms an event horizon beyond which light can never reach here. We can see objects currently beyond that event horizon, but only because we're looking at a past version of it when it hadn't yet crossed the horizon. We can see the sun, but only as it was 9 minutes ago, not as it is currently. All the more so for really distant objects.
 
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Trailblzn said:
Thank you for your reply, I genuinely appreciate it. Can you elaborate on which part of my question fundamentally misunderstands modern cosmology? The link http://preposterousuniverse.com/writings/cosmologyprimer/index.html is broken, just an FYI. I understand (or think I understand) the balloon analogy. What I think is correct, the universe is expanding in all directions, it is expanding faster the farther it is away from us. It is or can be expanding faster than the speed of light so the stuff at the edges of the universe may be expanding faster than any thing can travel to us. Is this the part that I misunderstand? Do you have any other suggested materials for me to read? I really appreciate your assistance.
This is all correct, except for the "may be expanding faster than the speed of light". It IS receding faster than c but no speeding tickets are issued because nothing has any proper motion faster than light. That is, it is not TRAVELING in the way you think it is. Spacetime is expanding which is not the same thing.

If you have read the link in my signature, you clearly didn't get it all, so I'd suggest another reading.

@Halc has just provided a good explanation of some of the rest of what you don't yet understand.
 
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https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
The formal paper is here. The Rutgers University news has published a story about an image being closely examined at their New Brunswick campus. Here is an excerpt: Computer modeling of the gravitational lens by Keeton and Eid showed that the four visible foreground galaxies causing the gravitational bending couldn’t explain the details of the five-image pattern. Only with the addition of a large, invisible mass, in this case, a dark matter halo, could the model match the observations...
Hi, I’m pretty new to cosmology and I’m trying to get my head around the Big Bang and the potential infinite extent of the universe as a whole. There’s lots of misleading info out there but this forum and a few others have helped me and I just wanted to check I have the right idea. The Big Bang was the creation of space and time. At this instant t=0 space was infinite in size but the scale factor was zero. I’m picturing it (hopefully correctly) like an excel spreadsheet with infinite...
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