And the type of nuclear decay each isotope undergoes before it reaches a state.

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The electroweak force is a synthesis of two previously identified forces of nature, electromagnetism (itself a synthesis, carried out in the 19th century, of the electric and magnetic forces), and the weak nuclear force, which governs radioactive decay.

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And this whole topic completely ignores the other, even rarer form of Heliem, the Isotope Helium3, which is formed only as a biproduct of the radioactive decay of the Tritium used in making nuclear missiles.

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Thermoelectric coupling uses heat from the decay of a radioactive fuel (as opposed to the full-scale nuclear fission which powers a reactor on Earth) as its energy source.

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