The Planck temperature is the unit of temperature in the system of Planck units. It has the value:

*T _{p}* = 1.41 × 10

In SI units, measurements of temperature are made in degrees Kelvin (usually given the symbol **K**). While the Kelvin is convenient for everyday usage, such as measuring the daytime temperature (around 300 K on a nice warm summer’s day) or a human’s normal body temperature (310 K = 37 degrees Celsius), a consequence of using SI units is that the fundamental constants take on values that are not always convenient for use in equations:

Speed of light | c = 299792458 m s^{-1} |

Gravitational constant | G = 6.673(10) x 10^{-11} m^{3} kg^{-1}s^{-2} |

Plank’s constant (reduced) | = h/2π = 1.054571596(82) x 10^{-34} kg m^{2} s^{-1} |

Boltzmann constant | k = 1.3806502(24) x 10^{-23}kg m^{2} s^{-2}K^{-1} |

The Planck temperature is found using the relationship between energy and temperature:

*T _{p} = E_{p}/k*

where *k* is the Boltzmann constant, and *E _{p} = m_{p}c^{2}* ( m

By redefining the base units for length, mass and time in terms of the Planck units, the fundamental constants have the values: *c* = *G* = = *k* = 1.

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