A photon is a particle that carries electromagnetic radiation. It is the fundamental unit of light.
- Thinking of photons as particles is useful for understanding the quantum nature of light.
- In the world of quantum physics, photons are the fundamental constituents of all forms of electromagnetic radiation, including light. They serve as the carriers of the electromagnetic force.
- Photons are elementary particles that have no mass and no electric charge. They are the quanta of the electromagnetic field, which is the fundamental field that describes electromagnetic interactions. Electromagnetic radiation, including light, is a manifestation of the electromagnetic field.
- Photons are the carriers of electromagnetic force because they are the only particles that can mediate electromagnetic interactions. When two charged particles interact electromagnetically, they exchange photons. The exchange of photons gives rise to the electromagnetic force.<
- Photons have no rest mass and always travel at the speed of light in a vacuum.
- Photons exhibit both wave-like and particle-like properties, a characteristic referred to as wave-particle duality. This duality is inherent to quantum particles, causing light to behave as a wave under certain conditions, as both waves and photons in others, and strictly as particles in yet others.