Does quantum electrodynamics (QED) have any practical use, or is QED a pure theory without any applications in real life?

Quantum electrodynamics (QED) is a highly accurate and successful theory that describes the interactions between light and matter. It has been used to make precise predictions in a wide range of physical phenomena, including the behavior of atoms and molecules, the properties of materials, and the behavior of particles in accelerators.

QED is also important in many practical applications such as the design of high-precision sensors, the development of new materials, and the creation of advanced technologies such as lasers and transistors. In addition, QED is an important part of the theoretical foundation for other areas of physics, such as quantum field theory and the Standard Model of particle physics.