A shaman is a tribal healer who can act as a medium between the visible world and the spirit world. Shamans are kind of a mix between priests and doctors. Like a priest, a shaman is a holy man who represents a religion â in this case, shamanism. Like a doctor, a shaman heals people â or at least claims to do so. If you're not into shamanism, you can use this term more generally: A really good teacher, especially one who works a little mysteriously, might be said to work like a shaman.
While the response is activated by the physics of light waves, the response itself is both physiological and psychological. Suppose that white light-i.e., light consisting of the full range of wavelengths within the visible light spectrum-is incident upon the retina.
Visible light is the most familiar form of a type of energy called electromagnetic radiation. Light is actually rather strange stuff. In some ways it behaves like a stream of particles (which we call photons), and in other ways it acts like a series of waves.