Planck Time

Planck time, abbreviated as \(t_p\), is the unit of time in the system of natural units known as Planck units.  It is defined as the time it would take a photon traveling at the speed of light to cross a distance equal to the Planck length.  Planck time is denoted by and is calculated using fundamental constants such as the speed of light, the gravitational constant, and the reduced Planck constant.

Planck time is significant because it represents the smallest meaningful interval of time according to our current understanding of physics.  At time scales shorter than the Planck time, the effects of quantum gravity are expected to become significant, and conventional notions of time might not apply.  It is also often used in theoretical physics, particularly in the context of attempts to understand the very early universe or the behavior of black holes.

 

Planck Time Formula
\( t_p = \sqrt{  h\;G \;/\; c^5 } \)     (Plank Tiume) \( h =  t_p^2  \;  (c^5 \;/\; g) \) \( G =  h \; c^5 \;/\; t_p^2  \) \( c = \sqrt[5]{  h\;G \;/\; t_p^2 } \)
Symbol	English	Metric
\( t_p \) = Planck Time (See Physics Constants)	\(sec\)	\(s\)
\( h \) = Planck Constant	\(lbf-ft\;/\;sec\)	\(J-s\)
\( G \) = Gravitational Constant	\(lbf-ft^2\;/\;lbm^2\)	\(N - m^2\;/\;kg^2\)
\( c \) = Speed of Light in a Vacuum	\(ft\;/\;sec\)	\(m\;/\;s\)