# Planck length and the speed of light (1 Viewer)

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#### helenk

How can the Planck length and the speed of light both be universal constants? Will the Planck length change depending on your frame of reference?

:)

#### rhenretta

Planck length is based on 3 constants, none of which change due to speed

$$\ell_{p}=\sqrt{\frac{\hbar G}{c^3}$$

Since $$\hbar$$ , G, and c are all constants, planck length also remains constant

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