photonsspecifically

Photons are fundamental particles that represent the quantum of the electromagnetic field. They are the force carriers of the electromagnetic force. Photons are massless, have no electric charge, and are always in motion at the speed of light in a vacuum. They exhibit wave-particle duality, meaning they can behave as both waves and particles depending on the experimental setup. As particles, they can be thought of as discrete packets of energy.

The energy of a photon is directly proportional to its frequency and inversely proportional to its wavelength. This relationship is described by the Planck-Einstein relation, E = hf, where E is energy, h is Planck's constant, and f is frequency. Photons are the constituent elements of all light and all other forms of electromagnetic radiation, including radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.

When an atom or molecule absorbs or emits energy, it does so in discrete packets, which are photons. This process is fundamental to many phenomena, such as photosynthesis, the photoelectric effect, and the operation of lasers. Photons are detected by various instruments, such as photomultiplier tubes and photodiodes, which convert the incident photon energy into an electrical signal. Their study is central to quantum mechanics and has led to numerous technological advancements.