Question

What are photons? What role did Einstein's explanation of the photoelectric effect play in the development of the particle-wave interpretation of the nature of electromagnetic radiation?

Short answer

Photons are quantum particles of light and electromagnetic radiation with no mass. Einstein explained the photoelectric effect, showing that light consists of discrete wave packets (photons) that transfer energy. This explanation bolstered the particle-wave interpretation of electromagnetic radiation.

Step-by-step solution

Define Photons

Photons are elementary particles, the quantum particles of light and all other forms of electromagnetic radiation, and the force carrier for the electromagnetic force. They possess zero mass and exist in vacuo traveling at the speed of light.

Explain Einstein's Photoelectric Effect

Einstein's photoelectric effect is the observation that many metals emit electrons when light shines upon them. Einstein explained this by proposing that a beam of light is not a wave propagating through space, but rather a collection of discrete wave packets (photons), each with energy. This energy is transferred to electrons in the metal.

Discuss the Particle-Wave Nature of Electromagnetic Radiation

Einstein's explanation of the photoelectric effect contributed to the development of the particle-wave interpretation of electromagnetic radiation. This interpretation acknowledges that electromagnetic radiation exhibits properties of both particles and waves. This dual nature was a major contribution to the development of quantum mechanics, explaining the interaction between light and matter.