Dark Matter and CP

  • A
  • Thread starter kelly0303
  • Start date
  • #1
275
15

Main Question or Discussion Point

Hello! I read several papers about different model of DM beyond basic WIMPs and axions but haven't found a lot about DM effects on baryon asymmetry. I was wondering, is it possible to have a type of DM that decays (or at least it did a lot in the past) preferably more to matter than antimatter? Or is there some fundamental symmetry that prevents this? Also if you know some papers that talk about this, I would really appreciate if you can point me towards them. Thank you!
 

Answers and Replies

  • #2
Orodruin
Staff Emeritus
Science Advisor
Homework Helper
Insights Author
Gold Member
16,817
6,626
You may be interested in the concept of asymmetric dark matter in general. The idea behind it is to make dark matter more similar to matter in the sense that the DM abundance is due to an asymmetry in the dark sector similar to the baryon asymmetry in the visible sector. Within this class of models there are several different ways in which the dark and baryon asymmetries can be generated together.

Also, another possible explanation of the baryon asymmetry is in terms of very heavy neutrinos (typically introduced to explain the lightness of the standard model neutrinos) decaying preferentially to matter over antimatter as you describe. However, the very same heavy neutrinos would typically not be dark matter.
 
  • #3
275
15
You may be interested in the concept of asymmetric dark matter in general. The idea behind it is to make dark matter more similar to matter in the sense that the DM abundance is due to an asymmetry in the dark sector similar to the baryon asymmetry in the visible sector. Within this class of models there are several different ways in which the dark and baryon asymmetries can be generated together.

Also, another possible explanation of the baryon asymmetry is in terms of very heavy neutrinos (typically introduced to explain the lightness of the standard model neutrinos) decaying preferentially to matter over antimatter as you describe. However, the very same heavy neutrinos would typically not be dark matter.
Thank you for this reply! I read about asymmetric DM but as you said this is more of a parallel between baryons and DM, assuming DM has an antiparticle. I was wondering about a more direct implication (like the heavy neutrinos effect) in which DM doesn't necessary have an antiparticle (it is it's own anti particle), but it decays more to particles than antiparticles. In this case DM doesn't have to be asymmetric, or be subject to the same mechanism as the baryons, instead DM itself is the mechanism (or at least one of them) which leads to baryon asymmetry? Is there any such model out there?
 
  • #4
Orodruin
Staff Emeritus
Science Advisor
Homework Helper
Insights Author
Gold Member
16,817
6,626
Typically, if you use the asymmetry in the decay to produce baryons, then your decay rate must be too short for the particle to be dark matter (for which it needs to be stable on cosmological time scales).
 
  • #5
275
15
Typically, if you use the asymmetry in the decay to produce baryons, then your decay rate must be too short for the particle to be dark matter (for which it needs to be stable on cosmological time scales).
Ah I see. However, can't you have some sort of custodial symmetry? Like at high energies in the past the decay was allowed, but in the effective Lagrangian nowadays the decay is extremely suppressed (the higher terms that would allow it goes like ##\Lambda^{-n}##) so you can have stable DM now and yet lots of decays in the past?
 

Related Threads on Dark Matter and CP

Replies
1
Views
4K
  • Last Post
Replies
16
Views
4K
  • Last Post
Replies
8
Views
3K
  • Last Post
Replies
3
Views
2K
Replies
3
Views
1K
Replies
3
Views
3K
  • Last Post
Replies
5
Views
2K
Replies
0
Views
2K
  • Last Post
Replies
1
Views
764
Replies
5
Views
2K
Top