The duality of light, as described by quantum mechanics, is a well-established and experimentally confirmed concept. It may seem counterintuitive, but the evidence strongly supports the idea that light exhibits both particle-like and wave-like properties, depending on how it is observed and measured.
In certain experiments, light behaves as if it consists of discrete particles called photons. These experiments include the photoelectric effect, where light can eject electrons from a material, and the detection of individual photon interactions in certain detectors. These phenomena suggest that light can be thought of as a stream of discrete particles.
On the other hand, light also displays wave-like behavior in various experiments. For instance, it can diffract and interfere, forming patterns similar to what is observed with waves. This wave-like behavior is evident in phenomena such as diffraction gratings, interference patterns, and the double-slit experiment.
The duality of light is not a result of our measurements being flawed or incomplete; rather, it is a fundamental aspect of the quantum nature of light. The wave-particle duality is a broader concept that applies not only to light but also to other elementary particles, such as electrons and even larger molecules.
It is important to note that the wave-particle duality does not mean that light is both a wave and a particle simultaneously. Instead, it suggests that light can exhibit characteristics of both a wave and a particle, depending on the experimental setup and the type of observation being made.
Quantum mechanics provides a mathematical framework that successfully describes and predicts the behavior of light and other particles, incorporating their dual nature. While the duality of light may seem strange from a classical perspective, it has been extensively tested and verified through numerous experiments and is a fundamental principle in our understanding of the physical world.