A fair warning: There are spoilers within. Read at your own discretion.
Christopher Nolan’s interstellar is out this week, and us regular astronomers are finally getting to see what critics have been gushing about and calling “the most scientifically accurate movie ever” (ok, not those words, but if you’re reading this at some point in the far future, that was the general idea of the moment.) (If you’re reading this in the far past, DON’T BUY TICKETS ON THE TITANIC! IT LOOKS NICE BUT IT’S JUST NOT WORTH IT!)
Reviews of the movie seem to center around two critiques: One, exemplified by The AV Club, is that the movie is Christopher Nolan’s usual tricks – characters or scenes that load way up on the exposition, balanced with plot threads delayed until they can make their maximum impact, beautiful visuals, people saying pseudointellectual things, and neat one-liners. The other one is The Bad Astronomer’s review of the science in the movie (with a follow-up), which points out the numerous flaws in the science of the story – as well as the dialogue and plot, which he found far more problematic.
To get my first point out of the way: Interstellar does have some rather significant flaws with its science, so yes, it’s worth pointing that out before everyone goes gaga over its ‘perfection’. And yes, I found some of the dialogue to be of the clunky “We’ve got a quiet moment, let’s discuss the fundamental nature of the human race” variety. And it was clear while watching it how Nolan dragged out some of the plotlines so that everyone could betray everyone else at the same moment (for instance). And I don’t quite buy the explanation of how Coop went from “We didn’t know you existed” to “Flying our spaceship” in, like, a day.
But, overall, I liked the movie. And yet I’m a PhD astronomer with knowledge of how actual physics ought to work. How’d that happen?
Well, the science wasn’t that bad. The characterization wasn’t that bad (particularly Murph and TARS). Yeah, they killed the black guy and Anne Hathaway’s character spends pretty much the entire movie dependent on others and it fails the Bechdel test. A lot of the plot holes you can find online are actually answered in dialogue probably drowned out by the weird sound mixing, which let the music and sound effects drown out a surprising amount of dialogue in tense moments. It’s obvious that a lot of the decisions Nolan made were inspired by 2001: A Space Odyssey, Solaris, and even Disney’s The Black Hole.
When it comes to a story, the plot is the most important thing. Second most, believable characterization. Third-most comes science. Without a decent plot, there IS no story. You can make it scientifically accurate all you want, but if it’s incomprehensible or (worse) boring, you’re still MST3K fodder. For instance, the shots of the Endurance passing Saturn were accurate, but boring. I think they were actual Cassini shots, but someone definitely dropped the ball because they had a golden opportunity to show the size and immensity and coolness of Saturn and its rings, and unlike every other time in the movie, they didn’t. This guy has done a much better job.
Science falls under the category of “things that help you to understand the plot”. It’s definitely better when it matches the real world, because then I can use my personal experiences and learned knowledge to make sense of what is going on. But along those lines, what’s really MOST important is internal consistency. I believe the people behind Star Trek: The Next Generation referred to it as “keeping things consistently bogus”. It might be wrong for physics (or biology, or political science) as we know it, but as long as it’s predictable, I’m ok with it. In the Star Wars universe, The Force allows a trained Jedi to sense and react to things without seeing them, which means when Luke Skywalker jumps onto the Sail Barge in “Return of the Jedi”, I recognize that this is an actual battle strategy and not a suicidally foolish idea, and I’m not surprised that he can block blaster shots coming from all directions – at least until he’s really overwhelmed by the mayhem surrounding him and gets shot in the hand.
When something is internally inconsistent, I’m thrown out of the story. I can no longer trust that I have any idea what – or why – anything is going to happen. There’s a quintessential bad example: On Doctor Who, in Tom Baker’s debut episode as the Fourth Doctor, a bunch of techno-terrorists are holding the world hostage with a giant robot and a disintegration ray. The disintegration ray has been, well, disintegrating things left and right for three and a half straight episodes when the good guys lead by Brigadier Alistair Gordon Lethbridge-Stuart, capture the disintegration ray. Meanwhile, the giant robot is still a destructive menace that can’t be stopped by machine guns. What does the Brigadier do? He uses the disintegrator ray on the robot! Makes perfect sense, right? My eight-year-old self thought so. But no, the disintegrator ray makes the robot grow to enormous size, and the rest of the story rips off King Kong. Because… WHAT?
So I have no problem with three habitable planets in one star system, where the star is a supermassive black hole and all the (somehow not deadly) light is from the accretion disk. In the universe Christopher Nolan created for Interstellar, that works, and the plot needs that black hole to play with time dilation. What I DO have a problem with is that they can’t send information back through the wormhole because they’re too close to the black hole, and they establish that “not even light” can escape the black hole, but later Coop and TARS promise to transmit data FROM INSIDE THE EVENT HORIZON. (Fortunately, they don’t need to enact that doomed plan because they’re scooped up by the tesseract, and I figure an alien that can create wormholes that aren’t singularities or hidden inside a black hole, can do whatever they want). I DO have a problem with Michael Caine’s character holding out the information that only Plan B was supposed to work, because Coop and Brand would have accidentally returned to Earth and unnecessarily doomed the place if things hadn’t gone exactly as they did (maybe they were supposed to enact plan B anyway? It got lost behind the sound mix).
That stuff bothers me. The rest is just part of the entertainment.