Natural Units
Using dimensional analysis, it is possible to combine dimensional universal physical constants to define a system of units of measurement that has no reference to any human construct. Depending on the choice and arrangement of constants used, the resulting natural units may have useful physical meaning. For example, Planck units, shown below, use c, G, ħ, ε0 and kB in such a manner to derive units relevant to unified theories such as quantum gravity.
| Name | Dimension | Expression | Value (SI units) |
|---|---|---|---|
| Planck length | Length (L) | 1.616 199(97) × 10−35 m | |
| Planck mass | Mass (M) | 2.176 51(13) × 10−8 kg | |
| Planck time | Time (T) | 5.391 06(32) × 10−44 s | |
| Planck charge | Electric charge (Q) | 1.875 545 956(41) × 10−18 C | |
| Planck temperature | Temperature (Θ) | 1.416 833(85) × 1032 K |
Read more about this topic: Physical Constant
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