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View Full Version : Discussion: Mapping the Hidden Dark Matter



Fraser
2003-Nov-06, 11:24 PM
SUMMARY: Dark matter is an invisible halo of material that seems to surround every galaxy. Astronomers can't see it, but they know it's there by the effect of its gravity; there seems to be 10 times as much dark matter as regular matter. Until now, astronomers believed that dark matter probably formed an even mist of particles in space, but researchers from UC Berkeley and MIT have created a computer simulation of how dark matter might clump together into larger chunks of material.


Comments or questions about this story? Feel free to share your thoughts.

star-tled
2003-Nov-07, 01:48 AM
Could someone answer what is likely a very basic question for me?

I was reading in another publication that astrophysicists believe that quite a significant percentage of the composition of the universe is hydrogen.

Is that assumption also applied to dark matter?

Would positing another element or combination of elements account for some of the problems that are being encountered when trying to calculate it's characteristics or account for the gravitational and electromagnetic properties that it displays? :unsure:

Guest
2003-Nov-07, 07:00 AM
Again the "theory of dark matter" raises its ugly head. Dark matter is postulated as the cause of anomolies in the speed of the stars rotating in the galactic disk. The theiory is ineffective in explaining why the stars rotate at the rate that they do so now t"they" have postulated "dark energy". I understand that there are many cosmologists who want a review of the origional theory of gravity since some very small changes in its formulation will easily account for these anomolies. This is a very reasonable suggestion since the postulation of dark matter and dark energy still fail to explain the observable universe. It is time to go back and examine the basics. Maybe even go back to first causes and evaluate the assumption that the whole observable universe just happened. Perhaps even to find that the background radiation that is said to be an echo of the big bang is in fact the echo of God himself saying "let there be light".

Matthew
2003-Nov-07, 09:18 AM
We do not know what dark matter is. It could be normal, matter, but there is also likely to be other types of matter, like black holes. There is a thread here (Dark Matter/Energy). (http://www.universetoday.com/forum/index.php?showtopic=367&hl=dark%20matter&st=0) Check it out.