The Science of Interstellar

In September 2013, Ritchie Kremer, the property master for Interstellar (the person in charge of props) asked me for observational data that Romilly could show to Brand. Of course, I turned to the world’s best experts for help: Yang and Zimmerman. They quickly produced tables of Gargantua’s resonant vibration frequencies and also of the rates that the vibrations die out by feeding energy into gravitational waves—tables based on their own calculations using Teukolsky’s equations. Then they added fake observational numbers to go along with the theoretical predictions and I added pictures of Gargantua’s event horizon (or rather, the edge of its shadow), pictures from simulations by the Interstellar visual-effects team at Double Negative. The result was Romilly’s observational data set.

When Christopher Nolan filmed the scene where Romilly discusses his observations with Amelia Brand, Romilly wound up not actually showing her his data set. It was there on a table, but he didn’t pick it up. However, the data set is central to my science extrapolation of Interstellar.

Gargantua’s Resonant Vibrations

Figure 18.1 is the data set’s first page. Each line of data on that page refers to a single resonant frequency at which Gargantua vibrates.

^{Fig. 18.1. The first page of the data that Yang and Zimmermann prepared for Romilly to show to Amelia Brand. [Prop from Interstellar, used courtesy of Warner Bros. Entertainment Inc.]}

The first column is a three-number code for the shape of Gargantua’s vibrations and the picture is a still from a movie Romilly took, in my extrapolation of Interstellar, which verified that the vibrations had the predicted shape. The second column of data is the vibration frequency and the third is the rate at which this vibration dies out, as predicted by Teukolsky’s equations.[32] The fourth and fifth columns show the difference between Romilly’s observations and the theoretical predictions.

In my extrapolation Romilly finds a few anomalies, severe disagreements between his observations and the theory. He prints the disagreements in red. On page one of the data set (Figure 18.1), there is just one anomaly, but the disagreement is severe: thirty-nine times larger than the uncertainty in his measurements!

These anomalies might be helpful in “solving gravity” (learning how to harness the anomalies), Romilly thinks, in my extrapolation. He wishes he could transmit what he has learned to Professor Brand back on Earth, but the outbound communication link has been severed, so he’s frustrated.

Even more, he wishes he could see inside Gargantua, to extract the crucial quantum data embedded in its singularity (Chapter 26). But he can’t.

And he doesn’t know whether the anomalies he observed are encoding some of the quantum data or not. Perhaps, with the hole spinning so rapidly, some of the quantum data leaked out through the horizon and produced the anomalies. Maybe Professor Brand could figure that out, if only Romilly could transmit the data to him.

I say a lot more later (Chapters 24–26) about gravitational anomalies, and quantum data from inside Gargantua as the key to harnessing the anomalies. But that’s later. For now, let’s continue our exploration of Gargantua’s environs, turning next to Mann’s planet.

19 Mann’s Planet

After discovering that Miller’s planet is hopeless for human colonization, Cooper and his crew travel to Mann’s planet.

The Planet’s Orbit and Lack of Sun

I have deduced a plausible orbit for Mann’s planet from two things in Interstellar:

First, Doyle says the trip to Mann’s planet will require months. From this I infer that, when the Endurance arrives at Mann’s planet, it must be far from Gargantua’s vicinity where the trip began. Second, almost immediately after the Endurance’s explosive accident in orbit around Mann’s planet, the crew find the Endurance being pulled toward Gargantua’s horizon. From this I infer that, when they leave Mann’s planet, the planet must be near Gargantua.

To achieve both requirements, the orbit of Mann’s planet must be highly elongated. And to avoid the planet’s being engulfed by Gargantua’s accretion disk as it nears Gargantua, the orbit, so far as possible, must be far above or below Gargantua’s equatorial plane, where the disk resides.

^{Fig. 19.1. A possible orbit for Mann’s planet, computed using a highly user-friendly web application written by David Saroff; see http://demonstrations.wolfram.com/3DKerrBlackHoleOrbits.}