Noun
Planck frequency (plural Planck frequencies)
(physics) A repeating event that occurs once every Planck time, with a frequency of
F
p
=
1
2
π
c
5
ℏ
G
=
E
P
/
h
≈
2.952
×
10
42
Hz
.
{\displaystyle F_{p}={\frac {1}{2\pi }}{\sqrt {\frac {c^{5}}{\hbar G}}}=E_{P}/h\approx 2.952\times 10^{42}{\mbox{ Hz}}.}
this frequency is said to be the upper bound for the frequency of an electromagnetic ray or cosmic rays.