Why don't neurons regenerate?
Answers
Generation of Neurons in the Adult Brain. It has long been known that mature, differentiated neurons do not divide (see Chapter 22). It does not follow, however, that all the neurons that make up the adult brain are produced during embryonic development, even though this interpretation has generally been assumed.
Well neutron is not an elementary particle, it is made up of smaller electrically charged elementary particles called 'quarks'. A neutron is made up of one "top quark" and two "bottom quarks". Top quark has charge +2e/3 and bottom quark has charge -e/3,
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the total charge of neutron is +2e/3 - e/3 - e/3 = 0
The magnetic moment of neutron essentially comes from the motion of quarks within the neutron.
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A neutron acts like a tiny bar magnet or a current loop which means it has an intristic magnetic moment and field. The strength of neutron magnetic moment is very small though. Neutrons with parallel spins are like two bar magnets with parallel moments [S]= = =[N] attract [S] = = =[N].
Thus parallel spin neutrons will attract and anti-parallel spin neutrons will repel. The strong nuclear force inside nucleus in independent of charge but depends on whether the spins of the nucleons are parallel or antiparallel.
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Now back to the original question. A neutron unlike charge particle does not need to be in motion to produce magnetic field. A neutron is a magnetic dipole itself. The field/moment of neutron is due to the spin of its individual quarks.
When neutron is pulled in a strong magnetic field, it will not experience a force but it will experience a torque which will try to rotate it and align its moment parallel to the field. This is similar to the rotation of a bar magnet or current loop in magnetic field.
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Polarized neutrons :
The neutron interacts with magnetic fields via its magnetic moment. Beams of "polarized neutrons" whose moments all point in the same direction can be created. Polarized neutrons were first produced by the transmission of a beam of neutrons through an iron plate magnetized to saturation. Polarized neutrons have numerous applications in nuclear physics.