Why Does Neutron Precess Despite q=0?

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    Neutron Precession
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Discussion Overview

The discussion revolves around the precession of neutrons in a magnetic field, specifically questioning why neutrons, which have a net charge of zero, exhibit this behavior. The conversation touches on theoretical aspects of magnetic moments, the nature of neutrons, and the implications of quark composition.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions the precession of neutrons in a magnetic field, noting that their charge (q) is zero, which suggests the Hamiltonian should also be zero.
  • Another participant seeks clarification on the stability of neutrons and their behavior in magnetic fields, indicating a need for background information.
  • A different participant proposes that neutrons precess due to their internal structure, specifically the presence of charged quarks, suggesting that neutrons should not be treated as elementary particles.
  • One participant critiques a formula presented earlier as a classical oversimplification, proposing a more nuanced expression for the magnetic moment that includes the nuclear magneton and specific values for protons and neutrons.
  • A participant expresses interest in the effect of quark charge on neutron motion in a magnetic field and requests a citation for further reading.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on the reasons for neutron precession, with multiple competing views on the role of quark charge and the appropriateness of classical models in this context.

Contextual Notes

There are unresolved assumptions regarding the treatment of neutrons as composite particles versus elementary particles, and the implications of their magnetic moments in various theoretical frameworks are not fully explored.

Who May Find This Useful

Readers interested in particle physics, magnetic moments, and the behavior of composite particles in magnetic fields may find this discussion relevant.

joex444
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We all know that the magnetic moment is (gq/2m)J, so then why does a neutron precess in a magnetic field if q=0? This should cause the Hamiltonian to be 0.
 
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neutrons precess in a magnetic field?
neutrons aren't even stable alone... can you elaborate on the background?
 
Hmm... ok, so I think I figured it out. Even though it is uncharged, it has charged quarks. Unlike the electron, neutrons aren't elementary so I can't think of them in that way. This explains why it does precess, as my paper indicates you can actually observe the interfence pattern caused by a 2pi rotation (which introduces the new wavefunction to be the negative of the original).
 
Last edited:
Your formula (gq/2m)J is a classical oversimplification. For neutral (or charged) particles,
the magnetic moment is written as (mu)e/2m, where e is the magnitude of the electron charge, and e/2m (the nuclear magneton for hadrons) is just a convenient scale factor. In these units mu=+2.79 for the proton and -1.91 for the neutron.
 
Quark charge has an appreciable effect on the motion of a neutron in a B-field?
Thats cool... can you site the article?
 

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