Dark Matter and extra dimensions

[CaptDude]

I have considered the possibility that dark matter is so hard to find because it exists in extra dimensions. Before posting here I googled this, and found that some scientists postulate this exact possibility, while others consider that extra dimensions themselves cause the effects that are explained by dark matter.
Just wondering what the community has to say on this.

 

[Chronos]

I'm inclined to doubt dark matter exists in, or is somehow related to extra dimensions. The neutrino, while not widely considered to be the only species, is clearly a species of dark matter and is easily accommodated by the standard model without need for extra dimensions.

 

[ChrisVer]

The candidates for DM are a lot of particles. Neutrinos is the one (eg due to Planck data for the effective neutrino species), another is the axions (with the BICEP2 results this mainly concerns axions that originate after the PQ phase transition that occurred after inflation together with the decay of strings and domain walls coming from the PQ phase transition), the other is SUSY models (that can also contain the axion sparticles mixing with LSPs). The Kaluza Klein particles (Kaluza Klein DM such as Kaluza-Klein axions) is also a theoretical possibility that has been investigated, eg in Solar plasma and large Time Projection Champers as in DRIFT II detectors. And I guess you can find more if you search...

 

[CaptDude]

I have read about the many candidates for dark matter particles. But none of them have been found as yet. This post does not ask about those particle candidates. Maybe the fact I am not getting direct answers to the question asked in my post - is my answer. :)

 

[ChrisVer]

In fact your question cannot be answered. You ask for the view-points of people on a theory that has been proposed as a DM candidate. I'm saying the proposed candidates are a lot, and I gave you some references where you can search for your own question (extra dimensions), such as Kaluza Klein Dark Matter [Don't forget you have to compactify those dimensions], and even more specific about Kaluza Klein axions and the experimental investigations done on this ground.

Of course none has been verified yet, and that's why I am not sure you can find a more specific answer (only personal beliefs). As long as a theory is not verified it remains a candidate, it can be disfavored or not, but that's all.

 

[Chronos]

Permit me to restate that neutrinos are confirmed dark matter particles. Additional unconfirmed particles, or neutrino species, may be required to complete a dark matter model.

 

[ChrisVer]

well known neutrinos can only count for the Hot DM...

 

[CaptDude]

Good point and I agree with you wholeheartedly. However, all the dark matter candidates in the space/time of our universe are theories as well and there is a discussion on them. So I was hoping to gain some insight as to the possibility of the topic of this post having any mainstream credibility. I have been pondering this question for years. My thinking on it is as follows.
1) It would explain the "dark" in dark matter.
2) I have read about the problem of gravity being much weaker than the other three forces in our universe. Some theorists wonder if the force of gravity "leaks" into the extra dimensions needed for string theory to work. This would mean that gravity is weaker in the "localized" area of our space/time - but that when measured across all the extra dimensions, gravity would balance out with the strong force, weak force, and electromagnetism.
3) If this turns out to be true, then any particles wrapped up in the extra dimensions should be able to have their gravitational influence "leak" back into our universe as the source of dark matter.

 

[ChrisVer]

http://arxiv.org/abs/hep-ph/0207125v2 (2002)
Have a look in this...although it is kind of old...
or this which I find more explanatory and has some good references at the end:
http://www.lns.cornell.edu/~ljf26/aexam/kaluza

Also here:
http://conferences.fnal.gov/aspen05/talks/servant.pdf
in the 4th slide you can find some more literature references.

And for the KK axionic DM, you can check here
http://arxiv.org/abs/0705.0615 (2007)
The 4th chapter.

As for mainstream, I think since work has been done to look into the matter, it is not considered para-science... IMO I am in general a bit "closed" in accepting the extra dimensions since they seem to me too far away from being verified soon, so I prefer looking at things that seem [TO ME] closer to be detected...so I prefer looking at normal axions or SUSY candidates... I may as well be wrong :p...

 

[phinds]

Good point and I agree with you wholeheartedly. However, all the dark matter candidates in the space/time of our universe are theories as well and ...

Do you seriously think that neutrinos are just a theory?

 

[CaptDude]

http://arxiv.org/abs/hep-ph/0207125v2 (2002)
Have a look in this...although it is kind of old...
or this which I find more explanatory and has some good references at the end:
http://www.lns.cornell.edu/~ljf26/aexam/kaluza

Also here:
http://conferences.fnal.gov/aspen05/talks/servant.pdf
in the 4th slide you can find some more literature references.

And for the KK axionic DM, you can check here
http://arxiv.org/abs/0705.0615 (2007)
The 4th chapter.

As for mainstream, I think since work has been done to look into the matter, it is not considered para-science... IMO I am in general a bit "closed" in accepting the extra dimensions since they seem to me too far away from being verified soon, so I prefer looking at things that seem [TO ME] closer to be detected...so I prefer looking at normal axions or SUSY candidates... I may as well be wrong :p...

Thank you for taking the time to post the links. I really appreciate it. I found them to be a bit over my head, but informative, interesting, and helpful nonetheless.

 

[CaptDude]

Do you seriously think that neutrinos are just a theory?

To answer your question. I do not. Not sure how you came to that conclusion. What I posted was - However, all the dark matter candidates in the space/time of our universe are theories as well and there is a discussion on them. What I meant by this was that the problem of dark matter is far from being fully resolved. Neutrinos seem to be but a part of the puzzle. As the posts of Cronos and ChrisVer clearly state.

 

[ChrisVer]

Thank you for taking the time to post the links. I really appreciate it. I found them to be a bit over my head, but informative, interesting, and helpful nonetheless.

Probably then you should start from a normal introduction to Extra dimensions before looking into this topic itself, which can be considered more specialized.
But nevertheless, the reason for posting these links in that post, was to support my next point :

As for mainstream, I think since work has been done to look into the matter, it is not considered para-science.