Questions about magnetic monopoles

Click For Summary

Discussion Overview

The discussion revolves around the existence and implications of magnetic monopoles, particularly in the context of the standard model, Grand Unified Theories (GUT), and supersymmetry (SUSY). Participants explore theoretical predictions, experimental searches, and cosmological implications of monopoles.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants note that magnetic monopoles are not present in the electro-weak sector of the standard model and are primarily sought in GUT and SUSY theories, which predict them to be heavy (around the Planck mass).
  • One participant questions the rationale behind searching for heavy monopoles at the LHC and asks whether there are theories predicting lighter monopoles.
  • Another participant suggests that cosmological theories predominantly discuss monopoles from GUTs, questioning whether monopoles could also be constructed from SU(3) related to strong interactions or flavor symmetries.
  • A response clarifies that SU(3) does not carry intrinsic electromagnetic charge and that flavor symmetry is explicitly broken, implying no monopoles exist in SU(3).
  • It is proposed that if monopoles could be lighter than predicted by GUTs, it would suggest a gauge group with weaker coupling, framing GUTs as a falsifiable argument regarding monopole detection at current energy scales.
  • One participant emphasizes the importance of experimental exploration beyond theoretical predictions, citing the discovery of the muon as an example.
  • Another participant mentions that GUT theories predict monopoles to be created at high energies during an early cosmological era, suggesting they should still be detectable unless inflation has diluted their presence.

Areas of Agreement / Disagreement

Participants express a range of views regarding the existence and implications of monopoles, with no consensus reached on the necessity of searching for them or their theoretical underpinnings.

Contextual Notes

Participants highlight various assumptions, such as the dependence on energy scales for monopole detection and the implications of symmetry breaking in different theoretical frameworks. The discussion remains open to interpretation and further exploration.

phoenix95
Gold Member
Messages
81
Reaction score
23
So far as I know there are no monopoles in the electro-weak sector of standard model. So people look for it in the GUT and SUSY sectors. However, they are predicted to be heavy(order of Planck mass). There have been studies from LHC attempting to detect monopoles. So here are my questions:

1. If monopoles are too heavy to be detected at LHC, then why look for them? Are there theories why predict them to be lighter than GUTs? Or am I missing anything?
2. Why all cosmology theories only talk about monopoles of GUTs? One can construct monopoles from SU(3) of strong interaction and/or flavor as well, can't they?
 
Physics news on Phys.org
Should experimenters only look for things predicted by theory? We would never have discovered the muon that way.
 
  • Like
Likes   Reactions: ohwilleke, Paul Colby and phoenix95
I think I figured out the answers to my question:

phoenix95 said:
2. Why all cosmology theories only talk about monopoles of GUTs? One can construct monopoles from SU(3) of strong interaction and/or flavor as well, can't they?
SU(3) of the color, doesn't intrinsically carry an electromagnetic charge. Or to put it more appropriately: The electromagnetic charge is constructed from flavor generators of SU(3) and not color. But the flavor symmetry is explicitly broken. Hence there are no monopoles in SU(3) (flavor or color).

phoenix95 said:
1. If monopoles are too heavy to be detected at LHC, then why look for them? Are there theories why predict them to be lighter than GUTs? Or am I missing anything?
Well, if they do then it corresponds to a gauge group that has a weaker coupling compared to GUTs. It can also be viewed like this: GUTs simply present a falsifiable argument saying "Monopoles cannot be detected at present scales available", and the experiments are simply testing that.

I hope someone can correct me if I am wrong in any of the above.

Vanadium 50 said:
Should experimenters only look for things predicted by theory? We would never have discovered the muon that way.
I absolutely agree. Experimenters should be the impudent brats as they are since otherwise theorists can only be writing fantasies.
 
GUT theories predict that monopoles are created at high energies (but not as high as Planck energy) at an early cosmological era. If so, they should be still visible in the present Universe (unless inflation diluted them).
 
  • Like
Likes   Reactions: phoenix95

Similar threads

Graduate Fermions, Monopoles & Quantum Hall: New Advances
  • · Replies 12 ·
Replies
12
Views
5K
High School Preon quark models excluded by LHC
  • · Replies 7 ·
Replies
7
Views
3K
Graduate Questions about N=1 SUSY and Magnetic Monopoles
  • · Replies 4 ·
Replies
4
Views
4K
Graduate New ideas on confinement and meson masses from Brazil
  • · Replies 4 ·
Replies
4
Views
2K
Graduate Does Peter Woit's solution of Higgs' naturalness problem work?
  • · Replies 4 ·
Replies
4
Views
3K
Undergrad LHC run 2, does Supersymmetry worsen hierarchy fine tuning
  • · Replies 2 ·
Replies
2
Views
2K
Graduate How would *You* detect magnetic monopoles?
  • · Replies 7 ·
Replies
7
Views
2K
Undergrad Is there new LHC data on coupling constant running?
  • · Replies 1 ·
Replies
1
Views
3K
Graduate A method to detect fermionic magnetic monopoles?
  • · Replies 1 ·
Replies
1
Views
2K
Graduate Why are magnetic monopoles so heavy?
  • · Replies 4 ·
Replies
4
Views
3K