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Offline yor_on

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Dark matter
« on: 26/01/2009 21:13:15 »
According to Nasa 'dark matter' exist.
http://www.nasa.gov/home/hqnews/2006/aug/HQ_06297_CHANDRA_Dark_Matter.html

So what could it be?
A denser 'boiling' field of potential 'energy' creating virtual particles constantly?
Would that act as 'mass'?

Or are they wrong.
Any ideas?





 

Offline Vern

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« Reply #1 on: 26/01/2009 21:27:29 »
I read he article; it is impressive, but I haven't convinced myself that dark matter has to be something other than space debris that is not fusing. I've seen other reports that show that some galaxies spin the way Newton's gravity would require and some spin way too fast. So some galaxies have it and some don't.
 

Offline Vern

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« Reply #2 on: 26/01/2009 21:44:50 »
Quote from: yor_on
Or are they wrong.
Any ideas?
Okey; I'm good at speculation:) At least I think I am. Lets say we have a load of the stuff a neutron star is made of, but as a thin gas of these neutron star particles. Maybe each little particle is so dense that it zips right through normal particles without interacting except by gravity.

I can make such a particle by stripping away shell 2 of two of my pet speculative particles then slamming them together so that they bind via shells 3 and 4. :) Shell 2 is the outermost shell. Shell 3 is the next shell in and shell 4 is the dot in the center.

Edit: My pet speculative particles usually bind by slamming together so that shells 3 get trapped inside shells 2.
« Last Edit: 26/01/2009 21:51:03 by Vern »
 

Offline yor_on

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« Reply #3 on: 26/01/2009 23:01:12 »
But doesn't this say that it must be something else than 'ordinary debris' Vern?

"The hot gas in this collision was slowed by a drag force, similar to air resistance. In contrast, the dark matter was not slowed by the impact, because it does not interact directly with itself or the gas except through gravity.

This produced the separation of the dark and normal matter seen in the data. If hot gas was the most massive component in the clusters, as proposed by alternative gravity theories, such a separation would not have been seen. Instead, dark matter is required."

Are you 'creating' two photons in one in that idea?
 

Offline Vern

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Dark matter
« Reply #4 on: 26/01/2009 23:38:27 »
Quote
"The hot gas in this collision was slowed by a drag force, similar to air resistance. In contrast, the dark matter was not slowed by the impact, because it does not interact directly with itself or the gas except through gravity.
Yes; the article has the dark matter made of something that only reacts with normal matter via gravity. If that's true it would have to flow through normal matter. That's why I speculated that it might be super-small super-dense particles. It seems to me that they would also somehow need to violate the Pauli Exclusion Principle.
Quote
Are you 'creating' two photons in one in that idea?
No; I was creating a super dense super massive particle by just using shells 3 and four of the model. Most of the mass of the proton is contained in shells 3 and 4 of this speculative model.

Calculator Software Source code in C
« Last Edit: 26/01/2009 23:45:04 by Vern »
 

Offline yor_on

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Dark matter
« Reply #5 on: 27/01/2009 00:16:47 »
Ok, I see what you mean.
I'm so used to thinking of it as a 'photonic' idea.
thanks.
 

Offline Vern

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« Reply #6 on: 27/01/2009 00:43:13 »
Ok, I see what you mean.
I'm so used to thinking of it as a 'photonic' idea.
thanks.

I forgot to mention; if somehow shells 3 and 4 bound such that they were stable with just the two shells, the resulting particle would be charge neutral. And being neutral it might behave like a super massive neutrino.

Of course all that is very speculative and I'll change my mind if I see somethng better. Have you thought about the composition of the dark matter?
« Last Edit: 27/01/2009 12:21:15 by Vern »
 

Offline yor_on

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« Reply #7 on: 27/01/2009 13:26:31 »
To be honest:)

I was hoping that you people had ideas?
It seems very strange to me.

"cosmological models predict that if WIMPs are what make up dark matter, trillions must pass through the Earth each second. Despite a number of attempts to find these WIMPs, none have yet been confirmedly found."
http://en.wikipedia.org/wiki/Weakly_interacting_massive_particles

Another theory seems to rest on there being Higgs fields or similar?

"In scalar-tensor theories, scalar fields like the Higgs field couple to the curvature given through the Riemann tensor or its traces. In many of such theories, the scalar field equals the inflaton field, which is needed to explain the inflation of the universe after the Big Bang"

But they also use renormalization to explain it. "renormalization refers to a collection of techniques used to take a continuum limit. When describing space and time as a continuum, certain statistical and quantum mechanical constructions are ill defined. In order to define them, the continuum limit has to be taken carefully.

Renormalization determines the relationship between parameters in the theory, when the parameters describing large distance scales differ from the parameters describing small distances."

Isn't that a kind of approximation, with 'subjective' limits set by you and your peers?
I know it is a powerful tool in QED (quantum electrodynamics) though?

-----

On the other hand, inflation would make sense (to my ideas:) if there was something like a Higgs field propagating it just after that BB.
Even though I see it as a 'Qm effect' without specifying any special type of 'field':)
But it could make sense?

On the third hand :)
I'm not happy about 'gravity' consisting of 'particles'(?)
To me it seems more as a pure 'field'

Bent space sort of, but my math is rather horrendous so...
« Last Edit: 27/01/2009 13:34:52 by yor_on »
 

Offline Vern

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« Reply #8 on: 27/01/2009 13:41:31 »
Quote from: yor_on
To be honest:)

I was hoping that you people had ideas?
It seems very strange to me.
My idea above was my speculative notion; I just made it up in response to your post. Our peers have about as many speculative notions as there are peers. The WIMP idea seems to satisfy a lot of folks, but I don't like the renormalization aspect of it. It seems just an unnatural add-on to avoid infinite values that break the arithmetic.
Quote
Renormalization was first developed in quantum electrodynamics (QED) to make sense of infinite integrals in perturbation theory. Initially viewed as a suspect, provisional procedure by some of its originators, renormalization eventually was embraced as an important and self-consistent tool in several fields of physics and mathematics.
Notice how its originators were suspect of the theory but later students accepted it without question. That same thing happened with QM theory.
« Last Edit: 27/01/2009 13:43:29 by Vern »
 

Offline DoctorBeaver

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« Reply #9 on: 28/01/2009 00:59:16 »
Has anyone come across holeums?

Quote from the above site: "New research calls these stable gravitational bound states of PBHs "holeum", and leads to the conclusion that they form an important constituent of dark matter."

Or go to http://www.subplanck.com/01%20-%20Design/Links/02%20-%20Articles/23%20-%20Holeum.htm and click on " Holeum, Enigmas Of Cosmology And Gravitational Waves" in the main panel.
« Last Edit: 28/01/2009 01:04:09 by DoctorBeaver »
 

Offline yor_on

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« Reply #10 on: 28/01/2009 01:55:02 »
Yeah, it's an alternative idea it seems.
I was looking at black holes without event horizons and found the same site:)'

They seem quite serious to me.
http://www.astronomy.net/forums/blackholes2/messages/4846.shtml

But I'm in to deep with 'ordinary' Black holes for the moment.
And I can't seem to find my way out?

(Hmm, that might have cometh out wrong?)
Awh:)
 

Offline Vern

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« Reply #11 on: 28/01/2009 11:42:18 »
I saw the notion about Primordial Black Holes but didn't put too much weight to it. I suspect it will be one of the in-process ideas. But we have named them now. PBH and Holeium, so they will be around for awhile :)

Quote
Stable, quantized gravitational bound states of primordial black holes called Holeums could have been produced in the early universe and could be a component of the Super Heavy Dark Matter (SHDM) present in galactic halos. We show that Holeums of masses of the order of 10**13 to 10**14 GeV and above are stable enough to survive in the present-day universe. We identify such Holeums as promising candidates for the SHDM "X-particle" and show that the decay of such Holeums by pressure ionization can give rise to cosmic rays of all observed energies, including Ultra High Energy Cosmic Rays (UHECR). The absence of the GZK cut-off is explained by the galactic halo origin of the UHECR. We predict that the cosmic rays are a manifestation of the end-stage Hawking radiation burst of the primordial black holes (PBH) liberated by the ionization of Holeums. Antimatter detected in cosmic rays could be a signature of their Holeum origin.
 

Offline demadone

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Dark matter
« Reply #12 on: 29/01/2009 10:40:00 »
It may exist. It may be what we call a vacuum. Explains why light can be conducted. But I'm rather doubtful about dark matter being matter.
 

Offline DoctorBeaver

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« Reply #13 on: 29/01/2009 11:55:37 »
The universe is expanding and taking matter with it & that's why galaxies are moving away from each other (in general). Could the expansion of space between galaxies be causing some kind of pressure that holds them together rather than there being extra mass to do it? (An analogy would be the way pressure under water prevents you opening a car door)
 

Offline Vern

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« Reply #14 on: 29/01/2009 12:32:19 »
Quote from: DoctorBeaver
The universe is expanding and taking matter with it & that's why galaxies are moving away from each other (in general).
I know that this is generally accepted as fact in the scientific community, but keep in mind the problems that we must accept before we can hold this as fact. We have to accept that space itself is expanding at an increasing rate due to some mysterious force, or energy.

It seems that we hold the latter speculative notion as a given, but accept the former dependent notion as fact. :)
 

Offline DoctorBeaver

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« Reply #15 on: 29/01/2009 12:51:53 »
I think the evidence for the expansion of space is fairly conclusive. The only doubt is about what is causing it.
 

Offline Vern

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« Reply #16 on: 29/01/2009 13:18:14 »
I think the evidence for the expansion of space is fairly conclusive. The only doubt is about what is causing it.
The evidence does seem overwhelming. But the only evidence we have is photons that are billions of years old and have been through unimaginable trepidations.
 

Offline demadone

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« Reply #17 on: 29/01/2009 13:31:50 »
(An analogy would be the way pressure under water prevents you opening a car door)
Air prevents you from opening the door. That's why they conclude existence of dark matter.
 

Offline DoctorBeaver

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« Reply #18 on: 29/01/2009 15:10:02 »
(An analogy would be the way pressure under water prevents you opening a car door)
Air prevents you from opening the door.

The pressure outside the car, from the water, is greater than the air pressure inside. It is the pressure differential that makes it impossible to open the door.

Quote
That's why they conclude existence of dark matter.

Eh? I thought it was as a result of trying to establish why galaxies don't lose their stars.
 

Offline Vern

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« Reply #19 on: 29/01/2009 15:16:28 »
Quote
Eh? I thought it was as a result of trying to establish why galaxies don't lose their stars.
You can say it that way, but it seems kind of odd; the stars had to get where they are by the force of gravity. We used to simply say that some galaxies spin too fast. But it is true that according to Newton, stars in those too-fast galaxies should fly off into space.
 

Offline DoctorBeaver

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« Reply #20 on: 29/01/2009 15:19:07 »
Quote
Eh? I thought it was as a result of trying to establish why galaxies don't lose their stars.
You can say it that way, but it seems kind of odd; the stars had to get where they are by the force of gravity. We used to simply say that some galaxies spin too fast. But it is true that according to Newton, stars in those too-fast galaxies should fly off into space.


Exactly. So something is either pulling on them to hold them in place (gravity in the form of dark matter), or there is a pressure pushing them from outside the galaxy that is holding them there.
 

Offline Vern

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« Reply #21 on: 29/01/2009 15:23:59 »
Quote from: DoctorBeaver
Exactly. So something is either pulling on them to hold them in place (gravity in the form of dark matter), or there is a pressure pushing them from outside the galaxy that is holding them there.
This reminds me of the push-gravity scheme that was popular some years ago. I think it was Feynman's firm rejection of that notion that was its demise.
 

Offline DoctorBeaver

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« Reply #22 on: 29/01/2009 15:31:22 »
What I'm thinking is a bit different from that
 

Offline Vern

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« Reply #23 on: 29/01/2009 16:10:51 »
What I'm thinking is a bit different from that
Interesting; is it something you can describe?
 

Offline DoctorBeaver

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« Reply #24 on: 29/01/2009 17:09:22 »
What I'm thinking is a bit different from that
Interesting; is it something you can describe?

I'll try to write it out first then post it here if I succeed
 

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« Reply #24 on: 29/01/2009 17:09:22 »

 

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