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Author Topic: The Universe size paradox: how far is it from one side to the other?  (Read 2451 times)

Offline Fozzie

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We are told that the farthest object we can see is approx 14 billion light years away. So if we look in the opposite direction we could also see an object 14 billion light years away. Therefore, the distance between the two objects must be 28 billion light years? Or, due to the curvature of space, if we travelled straight to one of the objects and went past it, would we pop out on the opposite side of the universe?
« Last Edit: 06/11/2009 00:03:54 by chris »


 

Offline Vern

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My own view is that you would see the same type universe you see from where you are now. Various creation theories might have you at the edge of the universe. But you now have to double your numbers. :) We now know of objects that seem to be 28 billion light years distant.

Here's a Wiki link about it

Quote from: the Wiki link
Some quasars display changes in luminosity which are rapid in the optical range and even more rapid in the X-rays. This implies that they are small (Solar System sized or less) because an object cannot change faster than the time it takes light to travel from one end to the other; but relativistic beaming of jets pointed nearly directly toward us explains the most extreme cases. The highest redshift known for a quasar (as of December 2007[update]) is 6.43,[2] which corresponds (assuming the currently-accepted value of 71 for the Hubble Constant) to a distance of approximately 28 billion light-years. (N.B. there are some subtleties in distance definitions in cosmology, so that distances greater than 13.7 billion light-years, or even greater than 27.4 = 2x13.7 billion light-years, can occur.)
« Last Edit: 05/11/2009 13:17:07 by Vern »
 

Offline Vern

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Look what happens when you Google with this thread title as the search string. :) I am truly amazed. BenV must have Google in his pocket.

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The size of the universe paradox - Naked Scientists Discussion Forum
1 post - 1 author - Last post: 38 minutes ago
The Naked Scientists science forum supports the naked scientists podcast and radio show. Ask and answer science questions on any subject.
www.thenakedscientists.com/forum/index.php?topic... - 38 minutes ago - Similar

 

Offline litespeed

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Vern

Have you ever heard the proposition that space can expand at such a pace that light emitted from sufficient distances can not reach us because the total space expansion equals or exceeds the speed of light?
 

Offline Vern

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Yes; I have seen that one; but like a lot of hypothesis I ponder, I didn't give that one much credence. I suspect that space is nothingness, and as such is incapable of expanding or contracting. So what I expect to see is radio telescopes seeing red-shifted spectra of the elements in as low a frequency as can be achieved.

I don't think anyone has looked for such radio frequency spectra yet. There would be no funding for it because one just doesn't get funding to test for problems with the Big Bang scenario. My guess is that we should be able to find such spectra with red shifts indicating a hundred billion years distance or so.

 
 

Offline Nizzle

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But, if the universe is static, how come every galaxy in it is moving away from every other galaxy?
What's the driving force? And why aren't some galaxies moving closer to others?

Or is this a wrong assumption, and is the 'red shift' actually just tired light?

Today, tired light is remembered mainly for historical interest, and almost no scientist accepts tired light as a viable explanation for Hubble's Law.
« Last Edit: 06/11/2009 08:26:32 by Nizzle »
 

Offline Vern

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Quote from: Nizzle
But, if the universe is static, how come every galaxy in it is moving away from every other galaxy?
What's the driving force? And why aren't some galaxies moving closer to others?
I suspect that the universe is very dynamic, but not in the way proposed by the Big Bang scenario. Tired light is a simplification. The quote you posted is deceptive. It implies that Tired Light was once a more viable notion than it now is. Tired Light was attacked from its inception. If it could have  been outlawed it would have been. :) This is the kind of deceptive speak you find in all the Big Bang supporting reports. I see the Big Bang theory as springing from a deep down urge for a creation event. The link is to The Primeval Atom by Abbe Georges Lemaitre; the Catholic priest who started it all.

I am not sure exactly what is going on; I don't think anybody else is either, :)
 

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