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View Full Version : Why can't we see past the cosmological horizon?



Littlemews
2003-Dec-04, 07:56 PM
This is the last part of my research (1st question), and all my group members have agreed: "Beyond the cosmological horizon, we are looking back to a time before the universe had formed". So are they right? or wrong....

but I think it is a distance problem, cuz its too far away, and we dont have the technology to see.....

Littlemews
2003-Dec-04, 09:21 PM
Sorry 1 more question....
What is the Mass Density of a Open(Coasting) Universe, a Flat(Critical) Universe, and a Close(Recollapsing) Universe?

Thanks to Helping me out ><&#33;&#33;

Tinaa
2003-Dec-04, 11:23 PM
If I remember correctly, the more mass there is, the more gravity there is. If there is enough gravity to slow expansion, the universe is closed, and will collapse in on itself. If there is not enough matter the universe will keep expanding forever, which is the open universe theory. If the mass equals the critical density, the universe is flat.

QJones
2003-Dec-05, 12:45 AM
To your first question:

The Big Bang theory states that the universe started out really &#39;small&#39; and got bigger.

So, out at the edge of our vision (way back in the past), we&#39;re looking at the beginning of time - we can&#39;t see past it, because, well, there was nothing.

But the HUGE sphere of the edge of the universe that we&#39;re looking at, actually is a picture of a really, really small dot.

essentially, we can look at the quanta of the beginning of the universe. Any events we observe now could be due to minor variations in the beginning of this quanta.

As a quick (and rough &#33;) analogy - imagine that a balloon had a picture of something on it (like a dog) - but the dog looked normal when the ballon was uninflated.

If you blew up the ballon, you&#39;d have a huge, distored picture of a dog. You can extrapolate what the dog looked like without the balloon having been blown up.