https://bigthink.com/starts-with-a-bang/...e-neutral/
KEY POINTS: On all cosmic scales in the Universe, from planets to the cosmic web, it's the gravitational force that determines the structures we get, not the electromagnetic or nuclear forces. The nuclear forces are only short-range, but electromagnetism stretches just as far as gravitation does, and is ridiculously more powerful. This implies the electron and proton have not only equal and opposite charges, but equal and opposite numbers in the Universe. But why is this so? (MORE - details)
KEY POINTS: On all cosmic scales in the Universe, from planets to the cosmic web, it's the gravitational force that determines the structures we get, not the electromagnetic or nuclear forces. The nuclear forces are only short-range, but electromagnetism stretches just as far as gravitation does, and is ridiculously more powerful. This implies the electron and proton have not only equal and opposite charges, but equal and opposite numbers in the Universe. But why is this so? (MORE - details)