# Fundamental Physics/Photon

## Photon

Photon is defined as energy of a Quanta travels at speed of visible light

${\displaystyle E=hf=h{\frac {\omega }{2\pi }}=\hbar \omega }$
${\displaystyle p={\frac {h}{\lambda }}=h{\frac {k}{2\pi }}=\hbar k}$
${\displaystyle h=p\lambda }$
${\displaystyle \omega ={\frac {E}{\hbar }}}$
${\displaystyle k={\frac {p}{\hbar }}}$
${\displaystyle \hbar ={\frac {E}{\omega }}={\frac {p}{k}}={\frac {h}{2\pi }}}$

## Photon's states

Photon exists in 2 states .

Radiant photon at ${\displaystyle f_{o}}$ carries quantum energy of energy of visible light ${\displaystyle E=hf_{o}}$
Non radiant photon at ${\displaystyle f>f_{o}}$ carries quantum energy greater than energy of visible light ${\displaystyle E=hf}$ with f > fo

Photon cannot exist in 2 states at the same time . The chances of finding photon at any one state is one half . This is the uncertainty principle proposed by schroduinger which can be expressed mathematicaaly as

${\displaystyle \Delta p\Delta \lambda ={\frac {1}{2}}{\frac {h}{2\pi }}={\frac {h}{4\pi }}={\frac {\hbar }{2}}}$