[Physics of "Interstellar"]

When I first saw this movie, there was one big question I had. Why is the planet Miller not pulled into the Black Hole Gargantua by the gravitational force, and so I did some research and found out some cool stuff.

 

One of the main reasons Planet Miller isn't pulled into the black hole in spite of its proximity is that the adviser, Kip Thorne made sure that Gargantua was a rapidly spinning black hole—and it turns out that the physics of rotating black holes differ from non-rotating ones. The sheer speed of Gargantua's rotation means there is a single stable orbit just outside of Gargantua's event horizon that is very stable. However, Gargantua would have to fill half the sky in order for it to be so close.

 

With spinning black holes, the area where the time dilates as drastically as in the movie is expanded exponentially, which allows for a small area where an object can orbit.

 

 

Another cool thing about this movie is the the tidal waves on the planet miller. According to The Science of Interstellar by Kip Thorne, Miller's planet is shaped a little like a football, with one end constantly pointing at Gargantua. The waves are literally tidal waves, so it's not the waves coming toward you, it's the planet rotating under you and the fixed waves slamming into you. But because the planet doesn't rotate, the waves wouldn't slam into you. Fortunately, tidally locked planets can rock back and forth, and Thorne used this as a scientifically accurate loophole to explain tidal waves on a tidally locked planet. Also, because the water on Miller is mostly concentrated in the waves, you could have knee-high oceans, like the one shown in the film.