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Constants

Mathematical

  • pi, π
  • τ
  • e
  • golden_ratio, φ

Named numbers

Large numbers

  • hundred
  • thousand
  • million
  • billion
  • trillion
  • quadrillion
  • quintillion
  • googol

Unicode fractions:

  • ½, , , ¼, ¾, …

Colloquial:

  • quarter
  • half
  • semi
  • double
  • triple
  • dozen

Physics

Description Identifier Dimension
The speed of light in vacuum speed_of_light, c Velocity
The Newtonian constant of gravitation gravitational_constant, G Force × Length^2 / Mass^2
Standard acceleration of gravity on earth gravity, g0 Acceleration
The Planck constant planck_constant, Mass × Length^2 / Time
The reduced Planck constant h_bar, Mass × Length^2 / Time
Mass of the electron electron_mass Mass
Elementary charge (charge of the electron) elementary_charge, electron_charge ElectricCharge
Magnetic constant (vacuum magnetic permeability) magnetic_constant, µ0, mu0 Force / Current^2
Electric constant (vacuum electric permittivity) electric_constant, ε0, eps0 Capacitance / Length
Bohr magneton bohr_magneton, µ_B Energy / MagneticFluxDensity
Fine structure constant fine_structure_constant, alpha, α Scalar
Proton mass proton_mass Mass
Neutron mass neutron_mass Mass
Avogadro constant avogadro_constant, N_A 1 / AmountOfSubstance
Boltzmann constant boltzmann_constant, k_B Energy / Temperature
Stefan-Boltzmann constant stefan_boltzmann_constant Power / (Area × Temperature^4)
Ideal gas constant gas_constant, R Energy / (AmountOfSubstance × Temperature)
Planck length planck_length Length
Planck mass planck_mass Mass
Planck time planck_time Time
Planck temperature planck_temperature Temperature
Planck energy planck_energy Energy
Bohr radius bohr_radius, a0 Length
Rydberg constant rydberg_constant Wavenumber