How Does Time Work in 'Interstellar'? What About Wormholes & Blackholes? We Break It Down

(Warning: The following contains major spoilers regarding plot points in Interstellar.) While Interstellar is perfectly enjoyable on its own accord, a bit of homework might be necessary to fully understand and appreciate all the tenets of science fiction woven throughout. Questions amount as we watch Matthew McConaughey blast through a wormhole to the other side of the universe, spend an hour on an alien planet that amounts to seven years on Earth time, and take one fateful journey inside the most mysterious of constructs in known science: the black hole.

Since the Nolan brothers’ dry-as-store-brand-Matzo exposition can be tough to permeate at times, it doesn’t hurt to brave some extracurricular research into the aforementioned concepts. Just in case David’s index card diagram, Wes Bentley mathematical estimates, and a trippy montage of dark blurs and white specks didn’t clear things up for you, here are some broad strokes explanations of each of the sci-fi concepts entertained in Interstellar and how and why they had the effect that they did on the characters.

(Note: In the spirit of Interstellar , I wholly endorse eschewing all scientific explanation of light, time, space travel, gravity, wormholes, black holes, et al in lieu of the simple, “It’s all about love.”)

WORMHOLES

Though wormholes are probably the easiest of Interstellar’s sci-fi concepts to grasp. You find a wormhole in outer space — in the case of the film, right outside the rings of Saturn. You enter. You come out the other side in a different place entirely — another point in space, one that may have taken you years, centuries, eons to reach via traditional travel.

Simple enough to imagine, but it’s the physical illustration of the wormhole that is a little more complicated. If you take a step outside of the universe (just for a second, I’ll save your seat) and view the whole thing head-on as a tangible substance — for the purposes of this explanation, a thick fabric might be most conducive to easy visualization. Identify one point in/on the fabricverse. Now find another one, with miles and miles of sweet velour separating the pair.

Now, there are two ways to get from point A to point B — one: you can hoof it, but the universe is less permitting to this style of travel than a textile scale model might be. So go for option two: pick up the felt surrounding A, ditto that around B, and bring the two points together so that they touch. To the tiny denizens of your makeshift universe, nothing will have seemed to change… until you poke a hole straight through the unified points, connecting them via quick leap through this veritable tear in the universal material.

A personal favorite analogy: Mario Kart 64. Everybody knows that there’s a secret shortcut in the Wario Stadium level of Mario 64 that allows you to jump directly from one part of the course to another. Well, a wormhole is kind of like that. (Hey, it helps me.)

RELATIVE TIME

There are two mentions in Interstellar of specific conditions that render time “slower.” The first, as described by McConaughey to his weeping daughter in a misguided effort to comfort her, involves an observer traveling near the speed of light. First off, this doesn’t mean that time feels or appears any slower to the traveler in question — to him or her, the minutes, hours, or days would pass normally during travel; once the traveler slows down, however, he or she will notice that far more time has passed for those of us ambling about slowly. In short, the hot rod in question might have only felt a few days pass (and will have aged only as such), but would recognize years to have gone by for friends and family members, all of whom would be accordingly older.

Here’s why: Light is essentially our gateway into all comprehension of the universe and everything that happens therein. All conceivable information — everything we see and experience — is dictated to us by light. As such, imagine that light is an impossibly chatty friend explaining the details of a movie about your life to you over the phone: “Okay, so, right now, you’re sitting in your office. You’re reading a long-winded article about Interstellar. You’re blinking. You’re wondering how long you can go without blinking.” Every inconsequential detail is reported to you by this friend of yours, so you can only experience the movie as fast as your friend will recite its story. Furthermore (and this is an important detail), you are so enrapt in the description of this film that it seems like nothing else exists outside of your conversation.

And light is a dutiful friend — one who speaks quickly and constantly. In fact, since your entire understanding of everything and anything that might be happening in the universe/your incredibly boring biopic relies entirely on light’s narration, and there are no windows to the world outside of your own experiences under the regime of light/your endless phone call that it seems like light is always moving at a speed with a consistent distance from your own.

Light is also a bit of a showboat, never letting you think you’re closing in on its verbal illustrations in any way. In other words, no matter how fast you travel, light always seems to be traveling the same amount faster than you are. So, you can begin jogging, or sprinting, or piloting jets, or flying rockets at impossible speeds, but light will always seem to be zooming by as it always has. You can never “catch up” to light, or even gain on it. (Or so it seems.)

But give it a try and you’ll notice an oddity upon your return to normal speed. When traveling near the speed of light, you’ll feel yourself covering so much ground in so little time, blasting almost instantaneously from one point to an incredibly distant destination. But the casual observer won’t be able to see you reach your goal until light permits.

This is when that phone call metaphor comes back into play. No matter what some may deem “objective reality,” the only gateway of the whats and whens and wheres of the universe that your have is your chatty narrator, light. You can only see yourself reaching the finish line when light tells you such as happened; on the same token, your friends can only see you crossing the finish line when their respective narrators clue them into the happening.

But while you were traveling so fast as to, again, cover so much ground in so little time, your friends were patiently waiting for their perceptions of light to catch up. As you were traveling so much closer to the speed of light than any of them were, all light got a chance to show you was a quick race from one point to another. But back at normal speeds, far away from that of light, your friends got to see plenty more: light showed them all sorts of things in the interim period; it had more time to do so, since they weren’t riding its tail and pressuring it to stay on point. Time managed to show your friends a few hours worth of their lives; yours only showed you a few seconds.

Now, apply this on a grander scale: years to days, decades to weeks. We see this phenomenon take place in Interstellar when McConaughey and co approach the vicinity of a black hole — the second means by which relative time comes into discussion in the movie. Considering everything mentioned above about light’s dictation of all time and space, this one should be a quick explanation.

Heavy things are a pain in the ass to deal with. Picture the fabricverse from the wormhole passage again: light has to travel along this fabric to bring you the lot of your informational intake. But when there’s a tremendously heavy object sitting on the colossal fabric, light has to slink down into the resultant grooves and then skulk back up again just to reach you on the other side. A black hole is basically the biggest, heaviest, most obnoxiously intrusive object that can delay light’s progress. For all of the reasons explained prior, this delay of light results in a slowed passage of time in relation to those experiencing light and life outside of the black hole’s immediate neighborhood. As such, McConaughey’s trip to the outer banks of the dark nightmare costs him a whole lot of Earth years for just a few precious black hole hours.

BLACK HOLES

So what is a black hole? A theoretical doozy, for one. Basically, a black hole is the utmost pull of gravity in the universe: nothing can escape a black hole’s grasp, not even light (imagine light being too heavy for something, go figure). While this might not seem like a significant entity in a vacuum, the implications of a plane with no perceivable light — or a perception of light that we, as a race that cannot see inside a black hole, have never observed — are vast. As mentioned, light dictates time, life, everything. So what can exist inside a field where time, life, and everything are not dictated?

That is the question.

Images: Paramount Pictures (5)