Max Planck and the Planck Base Units

Planck	Base	Units
Name	Dimension	Expression	Value (SI units)
Planck length	Length (L)	$l_{\text{P}}={\sqrt {\frac {\hbar G}{c^{3}}}}$	1.616 229(38) × 10⁻³⁵ m
Planck mass	Mass (M)	$m_{\text{P}}={\sqrt {\frac {\hbar c}{G}}}$	2.176 470(51) × 10⁻⁸ kg
Planck time	Time (T)	$t_{\text{P}}={\frac {l_{\text{P}}}{c}}={\frac {\hbar }{m_{\text{P}}c^{2}}}={\sqrt {\frac {\hbar G}{c^{5}}}}$	5.391 16(13) × 10⁻⁴⁴ s
Planck charge	Electric charge (Q)	$q_{\text{P}}={\sqrt {4\pi \varepsilon _{0}\hbar c}}={\frac {e}{\sqrt {\alpha }}}$	1.875 545 956(41) × 10⁻¹⁸ C
Planck temperature	Temperature (Θ)	$T_{\text{P}}={\frac {m_{\text{P}}c^{2}}{k_{\text{B}}}}={\sqrt {\frac {\hbar c^{5}}{Gk_{\text{B}}^{2}}}}$	1.416 808(33) × 10³² K^[12]