When this value depends upon the polarity of light, different values of it can occur in a single material in a property known as (*) birefringence.
This value changes upon application of an electric field in the Kerr effect. Metamaterials have a negative value for this quantity which gains a complex part to account for absorption in opaque materials. When this value depends upon the polarity of light, different values of it can occur in a single material in a property known as (*) birefringence. The ratio of this quantity for two different materials is equal to the ratio of the angle of incidence and its namesake angle according to Snell's Law. For 10 points, name this ratio of the speed of light in a vacuum to the speed of a light in a given material.
This value changes upon application of an electric field in the Kerr effect.
index of refraction or refractive index (prompt on "n")