So everyone will be curious, what is the meson that transmits magnetic force?

The essence of magnetic force is also an electromagnetic phenomenon and cannot act in isolation. We know that electrons surround the atomic nucleus, which can spin and are also distributed outside the nucleus through the formation of electron clouds. The spin of electrons can generate spin magnetic moments, and the motion of electrons outside the atomic nucleus can also generate orbital magnetic moments.

The sum of these two magnetic moments will make the atoms appear magnetic. The spin direction and orbit of electrons determine the direction of magnetic moments.

However, in most objects in life, the electrons outside the atomic nucleus are paired, with one electron spinning down and the other up, so the spin magnetic moment can be offset. Even if there are unpaired electrons, such as atoms arranged in disorder, the magnetic moment generated by unpaired electrons will be offset at the micro scale, so they will not exhibit magnetism at the macro scale.

If there are unpaired electrons in atoms within an object and they are arranged in an orderly manner, the magnetic moments generated by the electron spin will be superimposed, exhibiting magnetism at a macroscopic level.