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Fraser
2004-Oct-08, 04:21 PM
SUMMARY: Researchers from Caltech have looked deep into space to a time when early material in the Universe was swirling towards the creation of galaxy clusters and superclusters. They did their measurements using an instrument in the Chilean Andes called the Cosmic Background Imager (CBI), which looks at the Universe when it was only 400,000 years old - a time before galaxies, stars, and planets had formed. By watching the motion of this material as it began forming larger structures, the researchers were able to confirm that dark matter and dark energy were having an effect even then.

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Mark Taylor
2004-Oct-08, 08:56 PM
Something that is hard to understand...........If telescopes are looking at light from the early universe, then they could be receiving light from say, matter that composes planet earth today. So how did we move so fast as to be ahead of our own light?

antoniseb
2004-Oct-08, 09:19 PM
Originally posted by Mark Taylor@Oct 8 2004, 08:56 PM
So how did we move so fast as to be ahead of our own light?
The Cosmic Microwave Background radiation was emitted about the time the universe was 380,000 years old, and so the photons we are seeing now from this were emitted by stuff that was several hundred thousand light-years away from the material that turned into us at that time. This stuff was moving away from us at about 99.9% the speed of light.

GOURDHEAD
2004-Oct-09, 01:13 PM
This stuff was moving away from us at about 99.9% the speed of light.


Then, now, or both? BB+380,000 years is sufficiently after the alleged inflation period for that kind of velocity of expansion.

antoniseb
2004-Oct-09, 01:22 PM
Originally posted by GOURDHEAD@Oct 9 2004, 01:13 PM
Then, now, or both?
Both. It was going away from us when emitted, and the photons took 13.7 billion years to catch up. There is no reason to think that that matter had any cause or ability to accelerate towards us after the photons were released. By the current theory, it would be going a little faster away from us now because of dark energy, but that effect is small compared to the built-in imprecision of my 99.9% statement.