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Nuclear Force seems to refer to Residual Strong Force.

If so, how could we refer to Strong Nuclear Force and Weak Nuclear Force?

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  • How about you only use "nuclear force" for distances longer than a fermi or so? – Cosmas Zachos Jun 29 '17 at 15:09
  • Is there a need for a collective term for them? "Strong and Weak Forces" is already concise and they're different enough from each other that it's unlikely to be necessary to say this a lot. – eyeballfrog Nov 30 '18 at 19:38

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The nuclear force is only one :

The nuclear force (or nucleon–nucleon interaction or residual strong force) is a force that acts between the protons and neutrons of atoms.

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The nuclear force is a residual effect of the more fundamental strong force, or strong interaction

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even though nucleons are made of quarks in combinations which cancel most gluon forces (they are "color neutral"), some combinations of quarks and gluons nevertheless leak away from nucleons, in the form of short-range nuclear force fields that extend from one nucleon to another nearby nucleon. These nuclear forces are very weak compared to direct gluon forces ("color forces" or strong forces) inside nucleons, and the nuclear forces extend only over a few nuclear diameters, falling exponentially with distance. Nevertheless, they are strong enough to bind neutrons and protons over short distances, and overcome the electrical repulsion between protons in the nucleus.

The adjective "weak" as used with "force" indicates the weak interaction responsible for neutron decays, i.e. beta decay in nuclei. It is not a nuclear force in the sense of holding the nucleus compact. It appears in weak decays of nuclei, but that is a historical description, because we now know that there exists a weak interaction, one of the four fundamental forces., which is responsible for the decay chain of quarks.

The decay of hadrons by the weak interaction can be viewed as a process of decay of their constituent quarks. There is a pattern of these quark decays: a quark of charge +2/3 ( u,c,t) is always transformed to a quark of charge -1/3 (d,s,b) and vice versa. This is because the transformation proceeds by the exchange of charged W bosons, which must change the charge by one unit. The general pattern is that the quarks will decay to the most massive quark possible, leading the the pattern

t -> b -> c -> s -> u <-> d

anna v
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    This answer is mostly correct. However, both the charged weak current (which you mention) and the neutral weak current (which you ignore) do contribute to the nuclear force as perturbations. The weak force within nuclei allows states with different spatial parities to mix, which allows phenomena like nuclei with mirror-asymmetric shapes. The theory of the purely hadronic weak interaction is pretty messy, and currently the field is experiment-driven. However, see this answer for an example of the weak neutral current as a scattering force. – rob Dec 10 '18 at 17:29
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    well, of course the electromagnetic and weak play a role in the models, it is just that the strong is so much stronger, and I tried to clear the two usages of strong. – anna v Dec 10 '18 at 17:53