Physical constants

[Constant]LAL_C_SI [Constant]LAL_EPSILON0_SI [Constant]LAL_MU0_SI [Constant]LAL_GEARTH_SI [Constant]LAL_PATM_SI [Constant]LAL_G_SI [Constant]LAL_H_SI [Constant]LAL_HBAR_SI [Constant]LAL_MPL_SI [Constant]LAL_LPL_SI [Constant]LAL_TPL_SI [Constant]LAL_K_SI [Constant]LAL_R_SI [Constant]LAL_MOL [Constant]LAL_BWIEN_SI [Constant]LAL_SIGMA_SI [Constant]LAL_AMU_SI [Constant]LAL_MP_SI [Constant]LAL_ME_SI [Constant]LAL_QP_SI [Constant]LAL_ALPHA [Constant]LAL_RE_SI [Constant]LAL_LAMBDAE_SI [Constant]LAL_AB_SI [Constant]LAL_MUB_SI [Constant]LAL_MUN_SI

The following physical constants are defined to have exact values. The values of $c$ and $g$ are taken from [1], $p_\mathrm{atm}$ is from [2], while $\epsilon_0$ and $\mu_0$ are computed from $c$ using exact formulae. They are given in the SI units shown.

Name	Value	Description
LAL_C_SI	$299 792 458 \mathrm{m} \mathrm{s}^{-1}$	Speed of light $c$ in free space
LAL_EPSILON0_SI	$8.8541878176203898505365630317107503\times10^{-12} \mathrm{C}^2\mathrm{N}^{-1}\mathrm{m}^{-2}$
		Permittivity $\epsilon_0$ of free space
LAL_MU0_SI	$1.2566370614359172953850573533118012\times10^{-6} \mathrm{N} \mathrm{A}^{-2}$
		Permeability $\mu_0$ of free space
LAL_GEARTH_SI	$9.80665 \mathrm{m} \mathrm{s}^{-2}$	Standard gravity $g$
LAL_PATM_SI	$101 325 \mathrm{Pa}$	Standard atmospheric pressure $p_\mathrm{atm}$

The following are measured fundamental physical constants, with values given in [1]. When not dimensionless, they are given in the SI units shown.

Name	Value	Description
LAL_G_SI	$6.67259\times10^{-11} \mathrm{N} \mathrm{m}^{2} \mathrm{kg}^{-2}$	Gravitational constant $G$
LAL_H_SI	$6.6260755\times10^{-34} \mathrm{J} \mathrm{s}$	Planck constant $h$
LAL_HBAR_SI	$1.05457266\times10^{-34} \mathrm{J} \mathrm{s}$	Reduced Planck constant $\hbar$
LAL_MPL_SI	$2.17671\times10^{-8} \mathrm{kg}$	Planck mass
LAL_LPL_SI	$1.61605\times10^{-35} \mathrm{m}$	Planck length
LAL_TPL_SI	$5.39056\times10^{-44} \mathrm{s}$	Planck time
LAL_K_SI	$1.380658\times10^{-23} \mathrm{J} \mathrm{K}^{-1}$	Boltzmann constant $k$
LAL_R_SI	$8.314511 \mathrm{J} \mathrm{K}^{-1}$	Ideal gas constant $R$
LAL_MOL	$6.0221367\times10^{23}$	Avogadro constant
LAL_BWIEN_SI	$2.897756\times10^{-3} \mathrm{m} \mathrm{K}$	Wien displacement law constant $b$
LAL_SIGMA_SI	$5.67051\times10^{-8} \mathrm{W} \mathrm{m}^{-2} \mathrm{K}^{-4}$	Stefan-Boltzmann constant $\sigma$
LAL_AMU_SI	$1.6605402\times10^{-27} \mathrm{kg}$	Atomic mass unit
LAL_MP_SI	$1.6726231\times10^{-27} \mathrm{kg}$	Proton mass
LAL_ME_SI	$9.1093897\times10^{-31} \mathrm{kg}$	Electron mass
LAL_QP_SI	$1.60217733\times10^{-19} \mathrm{C}$	Proton charge
LAL_ALPHA	$7.297354677\times10^{-3}$	Fine structure constant
LAL_RE_SI	$2.81794092\times10^{-15} \mathrm{m}$	Classical electron radius $r_e$
LAL_LAMBDAE_SI	$3.86159323\times10^{-13} \mathrm{m}$	Electron Compton wavelength $\lambda_e$
LAL_AB_SI	$5.29177249\times10^{-11} \mathrm{m}$	Bohr radius $a$
LAL_MUB_SI	$9.27401543\times10^{-24} \mathrm{J} \mathrm{T}^{-1}$	Bohr magneton $\mu_B$
LAL_MUN_SI	$5.05078658\times10^{-27} \mathrm{J} \mathrm{T}^{-1}$	Nuclear magneton $\mu_N$