# Yukawa interaction and four fundamental forces [closed]

What is the difference(or relation) between Yukawa interaction($\mu\bar{\psi}\phi\psi$) and the other four fundamental interactions(e.m., weak, strong and gravity)? Does it fall anywhere on the symmetry breaking scale starting from Big bang?
Edit:
How to understand Yukawa interaction with parallel to the other four forces? Now that Quantum Chromodynamics (QCD) is the theory that describes the interactions inside a nucleus, my understanding is: Yukawa theory was developed much before the advent of gauge theories to explain the nuclear interactions. So, is Yukawa theory redundant or obsolete? I know that Yukawa interaction now is used in Standard Model to describe the interaction between massless fermions and scalar Higgs boson.

## closed as unclear what you're asking by John Rennie, ACuriousMind♦, mpv, Qmechanic♦Feb 29 '16 at 12:25

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• Yukawa is not a gauge force, for a start. – Slereah Feb 29 '16 at 9:34
• I'm not sure what this question is asking for. A list of all the differences between a Yukawa interaction and a minimal gauge coupling would be too broad. Can you be more specific what you want to know? – ACuriousMind Feb 29 '16 at 10:26
• I am trying to understand how Yukawa interaction differs from the other four forces. Slereah started by clearing that it is a non-gauge force; we use it in the Standard Model in the Spontaneous Symmetry Breaking. May be this is the best way to ask: can it be derived from the other four forces directly or as an approximation as it is not fundamental? – user31694 Mar 6 '16 at 7:50
• Please reopen this post for better answering – user31694 Jan 18 '18 at 11:42