Relativistic Doppler effect invisible ultraviolet wavelengths, infrared light is blueshifted into the visible range. Precisely what changes in the colors one sees depends on the physiology of the human eye and on the spectral characteristics of the light sources being observed. The Doppler effect (with arbitrary direction) also modifies the perceived source intensity: this can be expressed concisely by the fact that source strength divided by the cube of the frequency is a Lorentz invariant This implies that the total radiant intensity (summing over all frequencies) is multiplied by the fourth power of the Doppler factor for frequency. As a consequence, since Planck's
In the House of Stone and Light (album) As stated in the EPK, "Shape the Invisible" is Page's favorite on his debut album. As described by him in his video EPK: "My favorite song is 'Shape the Invisible', purely because of what the lyrics say. I was reading a book about Leonardo DaVinci and he mentioned that this shape the invisible in a sentence, and I thought what a great title. And at the time I wrote the song, there is as there always is trouble in the world, and I really wrote it as a wish song." Also stated in the EPK by Page, about the song