Bright and dark states of light
Bright and dark states of light: The quantum origin of classical interference
This paper discusses detectable and undetectable photon states with the bright (detectable) states interacting with the observer and dark (undetectable) states remaining hidden.
This is important since it potentially is a new, complementary, or conflicting result with the double slit experiment of wave-particle duality.
We may not yet have the instruments to measure this type of dark photon.
I find this confusing and am reading to learn more.
Abstract
Classical theory asserts that several electromagnetic waves cannot interact with matter if they interfere destructively to zero, whereas quantum mechanics predicts a nontrivial light-matter dynamics even when the average electric field vanishes. Here, we show that in quantum optics, classical interference emerges from collective bright and dark states of light, i.e., particular cases of two-mode binomial states, which are entangled superpositions of multi-mode photon-number states. This makes it possible to explain wave interference using the particle description of light and the superposition principle for linear systems only. It also sheds new light on an old debate concerning the origin of complementarity.