Question related to tv show How the Universe Works

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    Universe Works
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Discussion Overview

The discussion revolves around the apparent contradiction between the estimated age of the universe and the observed distances of cosmic structures, specifically referencing the Sloan Wall and the concept of the observable universe as presented in the show "How the Universe Works." Participants explore the implications of cosmic expansion and the inflation theory.

Discussion Character

  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions how matter can be 100 billion light-years apart in a universe that is approximately 14 billion years old, given the light-speed limit.
  • Another participant suggests that the universe may have expanded faster than the speed of light during its early inflationary phase.
  • A different participant emphasizes that the age of the universe does not equate to its size, explaining that the observable universe is much larger due to its expansion.
  • One participant illustrates the concept of cosmic expansion by describing how two stationary objects can appear to move apart due to the expansion of space itself, without exceeding the speed of light.

Areas of Agreement / Disagreement

Participants express differing views on the interpretation of the universe's size and age, with no consensus reached regarding the implications of cosmic expansion on the distances of celestial objects.

Contextual Notes

There are unresolved assumptions regarding the definitions of the universe's age and size, as well as the mechanics of cosmic expansion that are not fully explored in the discussion.

ko_kyi
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This is probably a really stupid question, but I don't know where else to ask it.

I am a layman watching Science channel, the show "How the Universe Works" episode called Alien Galaxies. In it they described the large scale structure of the universe, and talked about the Sloan Wall, which is +100 billion light-years across. A quick wiki search says that an estimate of the age of the universe since the big bang is 14 billion years, more or less. How the hell can objects made of matter be 100 billion light-years apart in a 15 billion year old universe, if matter can't travel faster than light?

Thanks in advance for indulging my question.
 
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You are watching BS. It draws in viewers so they include it on TV, that's what television is all about.
 
I think in the very early stages, they presume that the universe expanded faster than the speed of light in the inflation theory
 
Curl said:
You are watching BS. It draws in viewers so they include it on TV, that's what television is all about.

In your own thread on solar roads you claim others who ignore details are "ignorant on all levels" and then you go and do the same here.

The age of the universe is not the same as the size of the universe.
The observable universe is thus a sphere with a diameter of about 28 billion parsecs (9.3 × 1010 light years).

http://en.wikipedia.org/wiki/Observable_universe#Size

That's 93 billion light years across - and this only the observable universe.

This is down to the expansion of the universe.

Although two objects can be moving away from each other slower than the speed of light, the space inbetween them expands - giving the appearance they are traveling faster than the speed of light and increasing the distance between them further than would be possible in the given travel time.

If you imagine two objects stationary in space relative to each other, with the space between them expanding at a rate of 1m per year. After a million years they'll be 1,000,000m further apart than they originally were without ever moving.
 
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