Planck Time  The Planck time is the fundamental unit of time in
the system of Planck Units. It has the value:  tp = 5.39 × 10-44
s  In SI units, measurements of time are made in seconds
(usually given the symbol s). Although using seconds is
convenient for everyday life, such as measuring the time it
takes for an athlete to sprint 100 metres or the duration of a
phone call, it becomes less practical when we discuss the
sequence of events that happened in the very early Universe
(such as the onset of inflation that occurred 10-35s after the
Big Bang).  A consequence of using seconds to measure time is
that the fundamental constants take on values that are not
always convenient for including in equations:  Speed of light c
= 299792458 m s-1 Gravitational constant G = 6.673(10) x 10-11
m3 kg-1s-2 Plank’s constant (reduced) $ \hbar $ = h/2π =
1.054571596(82) x 10-34 kg m2 s-1 Boltzmann constant k =
1.3806502(24) x 10-23kg m2 s-2K-1  The Planck time is derived
dimensionally using combinations of these fundamental