The theory that explains the behavior of photons is called quantum electrodynamics (QED). This theory describes the interactions between photons and charged particles, such as electrons, and is considered one of the most successful theories in physics.
According to QED, photons exhibit both particle-like and wave-like behavior. This is known as wave-particle duality. The particle-like behavior of photons is described by their discrete energy levels, while their wave-like behavior is characterized by their wavelength and frequency.
Yes, QED can explain light interference. According to the theory, photons are constantly interacting with each other and with other particles in their path. This interaction results in the characteristic interference patterns observed in experiments.
Virtual particles are an essential part of QED. These particles, such as virtual photons, are constantly being created and destroyed in the quantum vacuum. They play a crucial role in the interactions between photons and charged particles.
QED is a more advanced and accurate theory compared to classical electromagnetism. While classical electromagnetism can describe the behavior of macroscopic objects, QED is necessary to accurately describe the behavior of subatomic particles, such as photons. QED incorporates and extends the principles of classical electromagnetism, making it a more comprehensive theory.