Model explaining the spiral arms without the need of dark energy

[Breakable]

http://www.forbes.com/sites/startswithabang/2015/12/12/ask-ethan-why-arent-spiral-galaxies-more-wound-up/

[Chuctanunda]

Correct me if I’m wrong, but I believe the spiral arms of galaxies rotate like the hands of a clock. If these were gravity generated then the outer reaches of the spirals would be accelerating faster than the inner. Dark matter is proposed as the counterbalance. With a plasma filament origin of these spirals, no need to assume dark matter. Does this sound right?

ScienceDaily.com link: http://www.sciencedaily.com/releases/2015/03/150305110346.htm describes the European Space Agency’s PLANK satellite mission results regarding Dark Matter. Are these guys barking up a wrong tree, based on false preconceptions? They seem so sure they’re on to something. If BBNH is right, they would seem to be wasting their time.

[JimmyT]

No, I’m afraid you misunderstand the way orbital mechanics works. It’s not like a rigid clock hand. It’s objects independently falling toward the center of mass of the galaxy. The forward momentum of these objects causes them to orbit. Their speed however does not increase as their distance from the center of mass increases. Their speed decreases with the inverse square of the distance from the center. It’s a flattening out of this orbital velocity (rather than a decrease) which makes astronomers postulate dark matter. The only way to get away from this idea is to somehow modify the inverse square law of the force of gravity. This has been tried by astrophysicist’s, but results in even greater complexity than the dark matter idea. And if you enbrace the idea that the simpler idea is usually the correct one, then right now the dark matter idea has it.

I should have worded that differently. The speed of orbiting objects still decreases with increased distance from the apparent center of mass of galaxies. Just not as fast as predicted by Kepler.

[Chuctanunda]

Thank you for the reply. I guess I have trouble visualizing the motion of stars in a spiral galaxy. My understanding of BBNH postulates dark matter as a fudge factor to explain why galaxy arm rotation isn’t as expected, based on Big Bang physics. BBNH then suggests plasma filament formation as the explanation. I just wonder if they have blinders on searching for the dark matter to support their Big Bang assumption, and not looking at plasma physics with an open mind. Can you shed light on the current state of advancing the plasma physics explanation?

[JimmyT]

You might want to go to you tube and watch Arthur B. McDonald’s talk about neutrinos. He is last years winner of the Nobel prize in physics. Towards the end of the talk he mentions that they are going to start using some of their equipment to try to detect WIMPS. In the opinion of many researchers WIMPS represent the best candidate for dark matter.

[Chuctanunda]

Is there any validity, in your opinion, to the notion that spiral galaxies are formed by plasma filamentation ? I understand the earnest search for dark matter. But if plasma filamentation offers a better fit, isn’t the seemingly endless search for this proposed dark matter rather a fools errand?

[JimmyT]

Yes, I think it’s quite possible that filamentation could be explained by electromagnetic forces. I don’t think you can explain the velocity curve that way. (If anyone knows better say so.) I’m no expert on this stuff.

[Lerner]

I’m busy trying to make filaments in the lab, but I just want to say that others have been doing more work on this observationally and the outer velocity curves of spirals, which are based on radio observations that measure the velocity of plasma, not stars, can be explained by the magnetic fields that are observed. At some point I’ll post the relevant papers. The one place where magnetic fields do not seem adequate for confining the mass of hot plasma observed is in clusters of galaxies. Some presently-unseen matter seems needed at the moment. However, that could be dim old stars in very old galaxies or even between galaxies that are too dim to be observed. This is more likely than exotic dark matter.

[Chuctanunda]

Thank you, Dr. Lerner. You put my mind at ease. I definitely don’t want you distracted from your progress on focus fusion energy. This is more important than winning the debate over dark matter.

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