Planck time
Quick Summary
The Planck time is the smallest possible unit of time, approximately (10^{-43}) seconds. It is derived from fundamental constants of nature: Planck's constant (h), the speed of light (c), and the gravitational constant (G). At the Planck time, the universe is thought to have been at its densest and hottest, with space-time requiring a quantum interpretation.1
Planck's constant (h) is a fundamental concept in quantum mechanics, introduced by Max Planck in 1900. It signifies that energy is emitted and absorbed in discrete packets called quanta, with the energy of a quantum being (E = h\nu), where (\nu) is the frequency of the radiation. The value of Planck's constant is approximately (6.626 \times 10^{-34}) joule-seconds.234
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- big-bang model
…a certain epoch called the Planck time. Scientists have yet to determine what prevailed before Planck time.
Read More…a certain epoch called the Planck time. Scientists have yet to determine what prevailed before Planck time.
Read More - cosmologySuperunification and the Planck era
This time, called the Planck time (Gh/c5)1/2, equals approximately 10−43 second. At the Planck time, the mass density of the universe is thought to approach the Planck density, c5/hG2, roughly 1093 grams per cubic centimetre. Contained within a Planck volume is a Planck mass (
Read MoreThis time, called the Planck time (Gh/c5)1/2, equals approximately 10−43 second. At the Planck time, the mass density of the universe is thought to approach the Planck density, c5/hG2, roughly 1093 grams per cubic centimetre. Contained within a Planck volume is a Planck mass (
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