inverted spectrum

The "inverted spectrum" is a thought experiment in the philosophy of mind that questions whether subjective experiences of color are necessarily tied to physical properties. It poses the puzzle of how to determine if two people's experiences of color are the same. For instance, if one person sees red as another person sees green, and vice versa, would they still use color terms identically?1

This thought experiment highlights the "explanatory gap" between physical processes in the brain and the subjective quality of conscious experience, known as qualia. It questions whether knowing all the physical facts about a person's brain is sufficient to determine their specific color experiences, or if there's an unbridgeable gap in understanding subjective perception. The concept is distinct from the scientific "inversion spectrum" related to molecular structure in quantum mechanics.213