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Fraser
2004-Mar-05, 07:11 PM
SUMMARY: British astronomers have used a radio telescope called the Very Small Array to probe the cosmic background radiation; an afterglow from the Big Bang that gives insights into the rapid expansion of the early Universe. By combining their results with data from the WMAP satellite, they were able to see how the expansion went when the Universe was only 10(-35) seconds old. They found that temperature and density varied much wider than traditional estimates.

What do you think about this story? Post your comments below.

Faulkner
2004-Mar-05, 07:15 PM
I'm having a cerebral aneurism just thinking about it!

John LaCour
2004-Mar-05, 08:41 PM
I've always thought that we have something fundamentally wrong with our cosmological model, and here is another possible spoiler. Each time a new instrument is deployed and the universe is measured by it, we seem to find that all our models need modifying.

Guest
2004-Mar-06, 09:45 AM
someone please bring me up to speed how do we know that the measured microwaves has a big bang genesis when lots of other systems in the universe also appear to transmit rf??

regards
ted uk

VanderL
2004-Mar-06, 12:06 PM
Previous ideas had suggested that, once the subsequent history of the Universe is accounted for, the distribution of fluctuations would be independent of scale.

Once the subsequent history of the Universe is accounted for? Subsequent of what?:( :o
And accounted for how?


However, the current results show that the fluctuations are most apparent at an angular scale of about 1/2 degree, the size of the Moon in the night sky. On both larger (the size of the Universe) and smaller (the size of a cluster of galaxies) scales, these variations in density and temperature are much less.

Now what, fluctuations in the CMB as large as 1/2 a degree?? That's not background now is it?
This article isn't explainig anything, at least not for me. What did they measure exactly and what models are contradicted?
Can anyone please explain in plain English what these people have found? :(
Cheers.

Victoria
2004-Mar-06, 01:00 PM
I suppose once the satellite is in place we will be updated...again. Gotta give the team some credit however for their research on such a controversial topic. :o

Nick4
2004-Mar-06, 04:12 PM
That thing in the photo is a radeo telescope?

Spacemad
2004-Mar-06, 09:58 PM
I find it fascinating how the astronomers are pushing back weekly the limits of the known universe! To get back to red shifts of 10 is truly amazing! :rolleyes: And to do it with ground based instruments is all the more remarkable!

How long before we see the "First Light" of creation? Surely we must have reached the limits by now of what is capable of being seen! :blink:

VanderL
2004-Mar-06, 11:49 PM
The idea was that the CMB is at redshift 17, so we still have a few years of finetuning ahead of us, but when we see a galaxy (even if it isn't fully formed) at redshift 10, there isn't much time for the formation of a galaxy. They have been pushing the limit, but it becomes more and more strained. We have to face it, either redshift isn't the distance measure that is assumed, or the whole inflationary model needs remodelling. Let's wait and see what the theorists can come up with. No doubt something invisible or outside probing with current instruments.

Cheers.

lindsay
2004-Mar-07, 09:35 AM
please help me understand. I am not sure if this is same story I heard about on science channel or nut, but... How or why are we able to see (in whatever sense of the word) what we can call "part of the first few moments". If this is true to what extent or how is that verbage to be preceived? I feel as though (and I may be mixing two different topics or ideas) we are being told that we can now see into the past, back into the begining stages of our univers. What exactly are they seeing? Is it the past, or are we seeing light, that with respect to expansion of space and time, is showing us what is the furhtest out there? Maybe I am confused with how I need to think of the space time issue. If we are seeing the begining stages then are we seeing the past or are we seeing the future to come? Sorry I cant explain that question any better. Non the less should there not be evidance of our own solar sytems creation if we can see so far as to see what is being considered part of the begining?
Help Me understand this please! :)
Jon
contact at otc@frontier.net

Graham
2004-Mar-08, 08:57 AM
Am I alone in worrying about the logical possibility of variations on the scale of the universe ("On both larger (the size of the Universe) and smaller (the size of a cluster of galaxies) scales, these variations in density and temperature are much less") when the universe is all you've got in which to show them?

VanderL
2004-Mar-08, 09:43 AM
For me that whole statement is puzzling, I just don't get it; what was measured exactly, what are the raw data and why is it claimed that something is out of whack when the something isn't explained?
Does anyone have any idea?

Cheers.

Faulkner
2004-Mar-08, 10:59 AM
I totally agree with VanderL here. Like many of these NASA "press releases", I find too many gaps & ambiguities... I mean, CMB fluctuations the angular size of the MOON in our skies? I thought they were looking for TINY fluctuations!?


someone please bring me up to speed how do we know that the measured microwaves has a big bang genesis when lots of other systems in the universe also appear to transmit rf??

Good comment, "Guest"! How do they differentiate the "background" microwaves from those emitted from galaxies & stars & black holes & quasars etc etc...(not to mention the "vacuum" itself!)...???