The behavior of light, as observed in the double-slit experiment and other phenomena, can indeed be puzzling. While light exhibits wave-like properties, it also exhibits particle-like behavior under certain conditions. This duality is a fundamental aspect of quantum mechanics.
In the double-slit experiment, when light is passed through two closely spaced slits, an interference pattern is observed on a screen placed behind the slits. This pattern arises from the interaction of light waves, indicating their wave-like nature. However, even when light is dimmed down to extremely low intensities, the pattern still emerges, suggesting that individual photons (particles of light) are interacting with the slits and forming the interference pattern. This demonstrates the particle-like behavior of light.
The wave-particle duality is a central concept in quantum mechanics, where particles such as photons can exhibit both wave-like and particle-like properties. It's important to note that describing light as a wave or a particle is an approximation that depends on the experimental setup and the nature of the observations being made.
In quantum mechanics, light is described as a quantum field, specifically as a superposition of particles (photons) and their associated wave functions. The behavior of light can be understood through the mathematical framework of quantum field theory, which allows us to make predictions and explain experimental results.
So, while it may be tempting to say that light is made up of particles based on its behavior in certain experiments, it is more accurate to say that light exhibits properties of both particles and waves, and our understanding of light is based on the framework of quantum mechanics and quantum field theory.