Consider two pairs of neutrons. In each pair, the separation between the neutrons is the same. Can the force between the neutrons have different magnitudes for the two pairs?

The answer can be yes as well as no. The fact is that if the neutrons have the same spin, then the force will be of same magnitude (repulsive) and if they have opposite spin, then force will be of different magnitude(attractive). Such forces are often referred to as tensor forces.


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