by rstevenson » Thu Jan 29, 2015 6:04 pm
Speculator wrote:rstevenson wrote:Speculator wrote:The galaxy appears to be travelling at a tremendous rate of speed through a medium of some sort .. that medium possibly Dark Matter.
Cygnus A is travelling through space fairly fast relative to the other galaxies in its local cluster, but not at what I'd call a tremendous rate.
Dark Matter is not a medium, and the dark matter that is near Cygnus A could more properly be described as
part of Cygnus A, just as dark matter in and around the Milky Way is part of the Milky Way.
Rob
Dark matter is not a medium, Rob? And yet it is said to make up 90% or whatever of the universe? Or perhaps you are sticking to one definition of the word 'Medium?'
Also, you seem to know an awful lot about Dark Matter considering it is not a proven anything just a possible theory of something.
When you talk about things moving through a medium, but what you describe as the medium -- in your case dark matter -- is actually part of what is moving, then yes, I think it's fair to say dark matter is not
the medium you're talking about. (I should have said "the", not "a" medium in the first place. I would have made myself clearer.)
Dark matter is rather mysterious, true. But it is well supported by observations, so it has to be dealt with as a real thing -- unless, that is, you wish to subscribe to one of the alternate theories of gravitation, which are themselves a great deal
less well supported than dark matter. In other words, if you incline to skepticism, be consistently skeptical.
Rob
[quote="Speculator"][quote="rstevenson"][quote="Speculator"]The galaxy appears to be travelling at a tremendous rate of speed through a medium of some sort .. that medium possibly Dark Matter.[/quote]
Cygnus A is travelling through space fairly fast relative to the other galaxies in its local cluster, but not at what I'd call a tremendous rate.
Dark Matter is not a medium, and the dark matter that is near Cygnus A could more properly be described as [i]part of[/i] Cygnus A, just as dark matter in and around the Milky Way is part of the Milky Way.
Rob[/quote]
Dark matter is not a medium, Rob? And yet it is said to make up 90% or whatever of the universe? Or perhaps you are sticking to one definition of the word 'Medium?'
Also, you seem to know an awful lot about Dark Matter considering it is not a proven anything just a possible theory of something.[/quote]
When you talk about things moving through a medium, but what you describe as the medium -- in your case dark matter -- is actually part of what is moving, then yes, I think it's fair to say dark matter is not [i]the[/i] medium you're talking about. (I should have said "the", not "a" medium in the first place. I would have made myself clearer.)
Dark matter is rather mysterious, true. But it is well supported by observations, so it has to be dealt with as a real thing -- unless, that is, you wish to subscribe to one of the alternate theories of gravitation, which are themselves a great deal [i]less[/i] well supported than dark matter. In other words, if you incline to skepticism, be consistently skeptical.
Rob