Gravity's Rainbow
Cover Art
NOTE: You can view the many variations of Gravity's Rainbow cover art through the years at ThomasPynchon.com
Thoughts on the Title
Andrew Graham:
Gravity acting on free flying objects tends to make them move in parabolas. A rainbow is a segment of a circle which is a different shape to a parabola.
As a rocket takes off under its exhaust power, it will be describing a curve of some sort but likely not yet following a parabola; it would only do so if carefully programmed to do so. Only once the fuel cuts out does it become ballistic, i.e., acted on primarily by gravity. The parabola it's now on carries it on upwards to a curved peak and then back down. Or at least this is an approximation of a parabola, friction necessarily deforming it. Thus a V2 did not follow a parabolic path, certainly not from the ground upwards. There are some details of their flight paths here
Thus "Gravity's Rainbow," if we take it to be referring to a V2 flight path, is only approximate to a parabola and can only ever be a deformed arc, or a deformed and de-coloured rainbow. The difference cannot be overcome by wishful thinking nor physics
Rainbows are also prism-like opening outs of white light. The refraction or bending of light in raindrops acts to different degrees on different colours (that is wavelengths or frequencies), thus creating the spread of colours which we see.
Gravity bends light but not like a prism as all frequencies are bent equally. However, as shown in the videos on this Wikipedia page, gravity does create rainbow like circles when acting as a lens. That is when astronomical objects pass behind other massive ones and the light from the former is bent around the latter.
Rainbows will also be circular when not restricted by the ground. With luck you can see this, in for example waterfall spray, or more prosaically with a garden hose, and a similar effect is created in the aureoles around aircraft shadows when they are cast onto clouds, known as "glories". So perhaps the gravity lensing effects are Gravity's Rainbows, created when light-emitting objects pass behind massive ones.
Gravity can also shift light in the red direction as it moves out from centres of gravity, creating (at a stretch perhaps) a not very enticing rainbow-like effect, gravity's rainbow here being linear and tending to the more hellish parts of the spectrum.
