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2002-Feb-21, 06:35 AM
Has anyone discovered evidence other than speeding edges of galaxies spinning too fast for the the mass observed?

GrapesOfWrath
2002-Feb-21, 11:22 AM
I once read a book by Dennis Sciama, written in the sixties I believe, that postulated almost the same amount of dark matter that cosmologists talk about today. His speculations were based upon Mach's principle, though.

The Bad Astronomer
2002-Feb-21, 06:03 PM
Yes. It is possible to measure the velocities of galaxies in large clusters. We can measure the amount of light emitted by the cluster too, and from that estimate the mass of the cluster by assuming that every solar mass of matter int he cluster emits the same amount of light as the Sun (a fair guess). The problem is, the galaxies are moving way too fast for the amount of mass estimated in this fashion. In other words, the galaxies are moving so fast they wouldn't remain in the cluster for very long; the cluster would lack the gravity to keep the galaxies bound to it.

Therefore, the cluster must have much more mass than assumed. This means most of the matter ust not be emitting light or else we would see it. Voila: dark matter.

aurorae
2002-Feb-21, 06:03 PM
On 2002-02-21 01:35, RPN wrote:
Has anyone discovered evidence other than speeding edges of galaxies spinning too fast for the the mass observed?


Apparently, the dark matter is distributed through the universe in the same pattern as galaxies.

see:
http://www.abc.net.au/science/news/stories/s437658.htm

DJ
2002-Feb-21, 11:57 PM
An interesting question: could dark matter be "dark" because it is something traveling faster than the speed of light?

DJ

davp
2013-Sep-02, 03:46 PM
An interesting question: could dark matter be "dark" because it is something traveling faster than the speed of light?

DJ

I don't know scientists' calculations, but I personally think that the blue stars of the outer regions are the older stars than the inner red bulge of galaxies! that what we are really looking at is time distortion created by the galaxies mases! and that gavity itself is really only an effect of mass slowing down time! and thats why the numbers don't add up! light is only constant in relation to time, but time can be slowed down by matter, causing gavity.

Swift
2013-Sep-03, 02:07 PM
I don't know scientists' calculations, but I personally think that the blue stars of the outer regions are the older stars than the inner red bulge of galaxies! that what we are really looking at is time distortion created by the galaxies mases! and that gavity itself is really only an effect of mass slowing down time! and thats why the numbers don't add up! light is only constant in relation to time, but time can be slowed down by matter, causing gavity.
Hi davp, welcome to CQ.

First, I hope you realize that you are responding to an 11 year old thread. Grapes of Wrath is the only one of these people who is a current contributor, and he goes by "Grapes" now.

Second, you are advocating (or maybe wildly speculating) on a non-mainstream idea. We have a specific part of the forum for that: ATM (Against The Mainstream). Please don't do such wild speculating outside of ATM.