It is a bad name for the Higgs boson that in the standard model of physics explains how some particles have mass.
The name God particle is from a book published in 1993, the idea of the particles in a 1964 paper and was confirmed in 2013. The name god particle is not endorsed by many scientists including Peter Higgs that it is named after. You can read more about the name at https://en.wikipedia.org/wiki/Higgs_boson#Naming
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