Derivation
While opinions vary as to its proper definition, the most common definition of a Planck particle is a particle whose Compton wavelength is equal to its Schwarzschild radius. This sets the relationship:
Thus making the mass of such a particle:
This mass will be times larger than the Planck mass, making a Planck particle 1.772 times more massive than the Planck unit mass.
Its radius will be the Compton wavelength:
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