Theory of the strong interaction verified: Supercomputer calculates mass difference between neutron and proton

The fact that the neutron is slightly more massive than the proton is the reason why atomic nuclei have exactly those properties that make our world and ultimately our existence possible. Eighty years after the discovery of the neutron, a team of physicists has finally calculated the tiny neutron-proton mass difference. The findings are considered a milestone by many physicists and confirm the theory of the strong interaction.

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