Planck time

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Named after Max Planck, in physics Planck time is the natural unit of time, denoted by tP. It is considered the smallest possible measurement of time.

<math>t_P = \sqrt{\frac{\hbar G}{c^5}} \approx</math> 5.391 × 10−44 seconds

where:

<math>\hbar</math> is the reduced Planck constant (or Dirac's constant)
G is the gravitational constant
c is the speed of light in a vacuum

The Planck time is the time it would take a photon travelling at the speed of light to cross a distance equal to the Planck length. However, this may not be taken as a "quantum of time". Within the framework of the laws of physics as we understand them today, we can neither measure nor discern any difference between the universe at the time it first came into existence and the universe anything less than 1 Planck time later.

The estimated age of the Universe (4.3 × 1017 s) is roughly 8 × 1060 Planck times.

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See also

Template:Planckunitsca:Temps de Planck es:Tiempo de Planck fr:Temps de Planck it:Tempo di Planck la:Tempus planckianum nl:Plancktijd ja:プランク時間 no:Planck-tid nn:Plancktid pl:Czas Plancka fi:Planckin aika vi:Thời gian Planck