Is the Universe bigger than we think?

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Discussion Overview

The discussion centers around the question of whether the universe is larger than current understanding suggests, exploring concepts related to cosmic inflation, the observable universe, and the implications of light speed limitations on our perception of cosmic distances. Participants engage with theoretical aspects of cosmology, including the nature of expansion and the age of the universe.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant suggests that the limitations of our detection abilities due to the expansion of spacetime may mean the universe is older than currently estimated.
  • Another participant argues that the universe is currently thought to be infinite in extent, which complicates the idea of it being "bigger" than we think.
  • There is a discussion about the observable universe being limited by the speed of light and the implications of inflation occurring faster than light, which may affect our understanding of cosmic distances.
  • Some participants clarify that the age of the universe is determined by the rate at which galaxies are receding from us, not solely by how far we can see.
  • One participant expresses confusion about the nature of cosmic expansion and seeks clarification on their understanding of the balloon analogy and the implications of objects receding faster than light.
  • Another participant corrects the notion that objects at the edge of the universe are merely "may be" expanding faster than light, stating that they are indeed receding faster than light due to the expansion of spacetime.
  • Several participants provide links to resources for further reading on cosmological concepts and inflationary theory.

Areas of Agreement / Disagreement

Participants express differing views on the implications of cosmic inflation and the nature of the universe's expansion. There is no consensus on whether the universe is larger than currently understood, and the discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Participants highlight limitations in understanding related to the nature of inflation, the observable universe, and the effects of light speed on cosmic observation. There are unresolved questions regarding the implications of accelerated inflation and event horizons.

Trailblzn
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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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