# Does anyone recognise this differential equation (from Gravity's Rainbow)?

In the novel Gravity's Rainbow by Thomas Pynchon, there is a chapter in which Slothrop (the main character) thinks about this equation:

$$\theta \frac{d^2\phi}{dt^2} + \delta^* \frac{d\phi}{dt} + \frac{\partial L}{\partial\alpha}(s_1-s_2)\alpha = -\frac{\partial R}{\partial\beta} s_3\beta\,.$$

It seems to be something to do with the V2 rocket, and yaw control. Does anyone recognise this equation from a book or research paper? What do the various variables stand for? He may have invented the equation, I suppose. How would one go about solving an equation like this? I find it strange that it contains both partial derivatives and total derivatives. However, there are equations in Hamiltonian mechanics like this.

Any help would be much appreciated. Thank you.

• I took the liberty of (a) including an image of the equation, and (b) specializing the title to indicate the Pynchon-source of the equation. – Joseph O'Rourke Mar 19 '17 at 2:53
• Googling, I stumbled on a paper by Magueijo and Smolin (2004, Classical and Quantum Gravity, Volume 21) called "Gravity's rainbow" - in context of relativity theory, they consider energy-dependent families of metrics and call these rainbow metrics. – მამუკა ჯიბლაძე Mar 19 '17 at 9:46
• Maybe somebody on the Physics or Space Exploration site could shed some light. – Jason C Mar 19 '17 at 16:11
• How can I re-post this on the Space Exploration site? – user947185 Mar 19 '17 at 18:43
• @user947185 Flag it for moderator attention and ask them to do it. – FFF Mar 22 '17 at 16:12

Schachterle, Lance, and P. K. Aravind. "The three equations in Gravity's Rainbow." Pynchon Notes 46-49 (2000): 157-170. Journal Link.

"In our view, Pynchon inscribes these equations into Gravity's Rainbow to challenge readers with yet another form of authority within the text."

Sorry—hit a pay wall...
Later: Got through the pay wall:

..........

• I myself don't accept their conclusion that this is "not a genuine mathematical expression." It seems unlikely Pynchon would concoct this without a basis in some real document. But I defer to "rocket scientists"... – Joseph O'Rourke Mar 19 '17 at 1:17
• There's a journal devoted entirely to the study of the works of Thomas Pynchon? And here I thought math journals were highly specialized... – Nate Eldredge Mar 19 '17 at 2:48
• @NateEldredge: "Pynchon Notes was a journal devoted to studying the works of Thomas Pynchon. Running from 1979 to 2009." 30 yrs. – Joseph O'Rourke Mar 19 '17 at 2:50
• Hmm. By the criterion of "two literary critics tried to pattern-match the equation against two textbooks and failed, so the equation is fake", I've a feeling that almost my entire career is fake. – David Richerby Mar 19 '17 at 9:07
• @DavidRicherby, "pattern-match" may be a slightly unfair way of putting it. Note that one of the authors, P.K. Aravind is a professor of physics users.wpi.edu/~paravind (though, not, so far as I can tell, an expert on rocket science), – j.c. Mar 19 '17 at 15:56