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Fraser
2003-Dec-12, 10:30 PM
SUMMARY: It was only a few years ago that astronomers shook up current models of the Universe with the theory of dark energy; which says that the expansion of the Universe is actually accelerating. But new evidence gathered by the ESA's XMM-Newton X-ray observatory has cast some doubt on the theory. By looking at distant galaxy clusters - up to 10 billion light-years away - the ESA astronomers found they contained more concentrated matter than the theory of dark energy would predict. If matter was so concentrated, the Universe can't be 70% dark energy.

View full article (http://www.universetoday.com/am/publish/dark_energy_doubts)

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

VanderL
2003-Dec-12, 10:51 PM
This only shows that the dark energy concept is on shaky grounds, but the real problem lies in the fact that the X-ray sources are thought to be very distant and thus would be very energetic. When all is catalogued and compared someday, we will see that the Universe really is the same in whatever direction we look. And much, much bigger than we think now.

Littlemews
2003-Dec-12, 10:59 PM
70%, i thought it was 90% :(

Matthew
2003-Dec-13, 03:15 AM
Originally posted by Littlemews@Dec 12 2003, 10:59 PM
70%, i thought it was 90% :(
Thats what I thought too, but thats what this evidence is now casting doubt over.

VanderL
2003-Dec-13, 03:00 PM
Maybe you're mistaking the amount of "dark energy" in the Universe for "dark matter", which is presumably 90+%?

Fraser
2003-Dec-13, 04:12 PM
Current theory is:

Dark Energy - 70&
Dark Matter - 25%
Regular Matter - 5%

VanderL
2003-Dec-13, 08:39 PM
Observational Science: 5%
Theoretical Science: 95%
I'd put my money on the observational guys.

Misha
2003-Dec-14, 03:42 AM
Fraser: What is the source of the story "New Doubts Over Dark Energy"? The links go nowhere and my searches of the web for this story have failed to turn up anything that would serve as the basis for this story. Maybe my searches were not successful because I just didn't look long enough, but I am puzzled. Everything that I see supports the Dark Energy idea.

Thanks
Misha

Fraser
2003-Dec-14, 04:09 AM
It was supposed to go here.

http://www.universetoday.com/am/publish/da...rgy_doubts.html (http://www.universetoday.com/am/publish/dark_energy_doubts.html)

damienpaul
2003-Dec-16, 04:49 AM
a quote from a student of mine:

the universe is:

1% life of 0.5% is looking for the other 0.5%
99% coco pops - his terminology for dark energy and the like

Damo