Planck Units
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Plank units are physical units of measurement defined
exclusively in terms of five universal physical constants, which are normalised
to 1 in the Planck unit measurement system. The five constants are:

The gravitational constant,

The reduced Planck constant,

The speed of light in a vacuum,

The Coulomb constant, i.e.

The Boltzmann constant,
References
Barrow, J.
(2003). The Constants of Nature. Vintage Books, London