/ 1 1 \ 2[pi]ne³Hp²v
= ½p ( --- - --- ) = -------------.
\ v1 v2 / m²(s² - p²)²
Since 1/v² = K0 + 4[pi]ne²/m(s² - p²), we have if µ is the refractive
index for light of frequency p, and v0 the velocity of light in vacuo.
µ² - 1 = 4[pi]ne²v²0 / m(s² - p²) (1)