About the properties of photons
- A photon is a single indivisible bundle (particle or wave) of energy within an electromagnetic field.
- A photon is an elementary particle and represents a quantum (plural =quanta) of light – the smallest quantity into which light can be divided.
- Whilst the field of optics often explains light in terms of waves, this description doesn’t always fit the evidence.
- Light sometimes exhibits wave-like behaviour, at others, it behaves like both waves and particles or just as particles.
Other properties of photons include:
- They have zero mass and rest energy. They only exist as moving particles.
- They are elementary particles despite lacking rest mass.
- They have no electric charge.
- They are stable.
- They carry energy and momentum which are dependent on the frequency.
- They can have interactions with other particles such as electrons.
- They can be destroyed or created by many natural processes, for instance when radiation is absorbed or emitted.
- When in empty space, they travel at the speed of light.