In quantum mechanics, light is described as a collection of particles called photons and as an electromagnetic wave. This dual nature of light is known as wave-particle duality.
According to the particle nature of light, photons are massless particles that carry energy and momentum. Each photon carries a discrete amount of energy, which is proportional to its frequency. The energy of a photon is given by the equation E = hf, where E is the energy, h is Planck's constant (a fundamental constant in quantum mechanics), and f is the frequency of the light.
On the other hand, the wave nature of light is described by the electromagnetic wave theory. In this description, light is an oscillating electromagnetic field that propagates through space. The wave properties of light, such as wavelength, frequency, and amplitude, are related to the electromagnetic field. The wave nature of light explains phenomena like interference, diffraction, and polarization.
It is important to note that light can exhibit both particle-like and wave-like behaviors depending on the experimental setup and the phenomena being observed. This wave-particle duality is a fundamental aspect of quantum mechanics and is not limited to light but applies to other particles as well.