IceCube search for the 'sterile neutrino' draws a blank

  • Context: Graduate 
  • Thread starter Thread starter kodama
  • Start date Start date
  • Tags Tags
    Neutrino Search
Click For Summary

Discussion Overview

The discussion revolves around the implications of recent null results in searches for sterile neutrinos and other beyond the Standard Model (BSM) physics candidates. Participants explore the ramifications of these findings for dark matter theories and neutrino physics, as well as potential future directions in research.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants note that null results do not diminish the value of research, as they help refine the search for viable hypotheses.
  • Examples of past null results, such as the Michelson-Morley experiment and proton decay, are cited to illustrate how null findings can guide future research.
  • There is a call for more promising approaches in BSM physics beyond merely fine-tuning existing models to evade experimental bounds.
  • Participants discuss the status of the sterile neutrino hypothesis, suggesting it may be increasingly unsupported by recent data.
  • One participant mentions that the null results constrain the allowable parameter space for models, complicating the invalidation of theories with many adjustable parameters.
  • Various dark matter candidates are proposed, including warm dark matter and self-interacting dark matter, with discussions on their stability and production mechanisms.
  • Questions arise regarding the potential for new particles, such as the X boson, and whether they are receiving renewed attention in light of recent findings.

Areas of Agreement / Disagreement

Participants express a range of views on the implications of null results, with no consensus on the future directions for BSM physics or the status of dark matter candidates. Some agree on the need for new approaches, while others remain skeptical about the viability of existing theories.

Contextual Notes

The discussion highlights limitations in current models and the challenges of distinguishing between various dark matter candidates, as well as the unresolved nature of some theoretical frameworks.

  • #31
kodama said:
feng proposes his boson is a spin-1 vector boson with axial and vectorlike currents

Nonzero-spin fields with nonzero VEV break Lorentz invariance.
 
  • Like
Likes   Reactions: kodama
Physics news on Phys.org
  • #32
nikkkom said:
Nonzero-spin fields with nonzero VEV break Lorentz invariance.

perhaps this boson has zero VEV to preserve Lorentz invariance
 
  • #33
Then how it generates neutrino mass?
 
  • #34
nikkkom said:
Then how it generates neutrino mass?

if there is more than 1 higgs field, perhaps neutrinos couple to a second set of higgs
 
  • #35
nikkkom said:
Higgs-like coupling (IOW: fermion to scalar field coupling) would require existence of RH neutrinos.

Depends on how "Higgs-like" it has to be. I don't see anything wrong in principle with a scalar field that couples only to left handed particles and thereby generates mass. It wouldn't be very Higgs-like, compared to the SM, but shouldn't be mathematically impossible.
 
  • #36
kodama said:
what kind of dark matter is left?

Fuzzy dark matter.

W. Hu, R. Barkana, and A. Gruzinov, “Cold and fuzzy dark matter,” Phys. Rev. Lett. 85, 1158–1161 (2000), https://arxiv.org/abs/astro-ph/0003365

One of the big conundrums is that the assumption of dark matter works extremely well on large scales for explaining the structure of the cosmos, but seems to fail to work on the scale of galaxies. One interesting idea how to fix this (without giving up on the established theory of gravity as MOND does) is to assume that dark matter consists of massive but extremely light particles, whose de Broglie wavelength is of the order of thousands of parsecs. This has the consequence that at around the scale of that wavelength the behaviour of this dark matter changes.

Now Edward Witten et al. have argued in more detail that this works really well, and consistent with existing null results on direct detection:

Lam Hui, Jeremiah P. Ostriker, Scott Tremaine, Edward Witten, "On the hypothesis that cosmological dark matter is composed of ultra-light bosons" https://arxiv.org/abs/1610.08297
 
  • #37
[URL='https://www.physicsforums.com/insights/author/urs-schreiber/']Urs Schreiber[/URL] said:
Fuzzy dark matter.

W. Hu, R. Barkana, and A. Gruzinov, “Cold and fuzzy dark matter,” Phys. Rev. Lett. 85, 1158–1161 (2000), https://arxiv.org/abs/astro-ph/0003365

One of the big conundrums is that the assumption of dark matter works extremely well on large scales for explaining the structure of the cosmos, but seems to fail to work on the scale of galaxies. One interesting idea how to fix this (without giving up on the established theory of gravity as MOND does) is to assume that dark matter consists of massive but extremely light particles, whose de Broglie wavelength is of the order of thousands of parsecs. This has the consequence that at around the scale of that wavelength the behaviour of this dark matter changes.

Now Edward Witten et al. have argued in more detail that this works really well, and consistent with existing null results on direct detection:

Lam Hui, Jeremiah P. Ostriker, Scott Tremaine, Edward Witten, "On the hypothesis that cosmological dark matter is composed of ultra-light bosons" https://arxiv.org/abs/1610.08297

does this fuzzy dark matter couple to higgs?
 

Similar threads

  • · Replies 13 ·
Replies
13
Views
4K
  • · Replies 24 ·
Replies
24
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 27 ·
Replies
27
Views
5K
  • · Replies 30 ·
2
Replies
30
Views
9K
  • · Replies 74 ·
3
Replies
74
Views
11K
Replies
5
Views
2K
  • · Replies 18 ·
Replies
18
Views
4K
  • · Replies 11 ·
Replies
11
Views
3K