I’ve been thinking about the Terminator series a lot lately. Victory I guess for the Terminator Salvation marketers. So I’m going to talk about time travel. (Mostly this will be my version of the same conversation everyone has after they see the movies, and the first one is 25 years old, so apologies if it isn’t exactly new ground.) The big question I have is this: is John Connor right when he says that “there is no such thing as Fate”?
There are a few different ways that time travel could work within a movie. I’ll pick out three:
- Time is a closed loop that can’t be changed. One cannot alter the present by going to the past. It already happened.
- Time exists as one open loop. The past can be changed. Such changes would be instant and unnoticed by a neutral observer in the present.
- Time travel is really dimensional travel. When one travels back in time one really moves to a parallel Earth-n that was identical to one’s home Earth-1 until the moment of arrival.
A Note on Canon
I consider only the theatrical releases of The Terminator and Terminator 2: Judgment Day to be canonical. The extended edition of T2 changes the game severely with some deleted scenes that were wisely cut. Terminator 3: Rise of the Machines and Terminator: The Sarah Connor Chronicles both introduce too many inconsistencies to be dealt with with rigid coherency, despite having their virtues. We’ll see about Salvation.
The Closed Loop
John gave me a message for you. Made me memorize it. “Sarah”… this is the message… “Sarah, thank you. For your courage through the dark years. I can’t help you with what you must soon face, except to tell you that the future is not set… there is no such thing as Fate, but what we make for ourselves by our own will. You must be stronger than you imagine you can be. You must survive, or I will never exist.” That’s all. (script)
If time exists as one closed loop, John Connor’s message is wrong. It’s a nice sentiment, and probably a necessary one for his mother to have some hope that she can raise her son to prevent Judgement Day, but ultimately it’s incorrect if time is inalterable. If the past cannot be changed, then the future is set in stone. Every action every person and machine makes is already set. Fortunately (though I sort of like the idea that Judgment Day is inevitable), the films gives us proof that this isn’t the case. From Terminator 2:
I need to know how Skynet gets built. Who’s responsible?
The man most directly responsible is Miles Bennet Dyson, Director of Special Projects at Cyberdyne Systems Corporation.
In a few months he creates a revolutionary type of microprocessor.
In three years Cyberdyne will become the largest supplier of military computer systems. All stealth bombers are upgraded with Cyberdyne computers, becoming fully unmanned. Afterward, they fly with a perfect operational record. […] The Skynet funding bill is passed. The system goes online August 4th, 1997. Human decisions are removed from strategic defense. Skynet begins to learn, at a geometric rate. It becomes self-aware at 2:14 a.m. eastern time, August 29. In a panic, they try to pull the plug.
And Skynet fights back.
Yes. It launches its ICBMs against their targets in Russia.
Why attack Russia?
Because Skynet knows the Russian counter-strike will remove its enemies here.
How much do you know about Dyson?
I have detailed files. (script)
This scene sets up the third act in the film, in which John, Sarah, and their terminator assault Cyberdyne and succeed in destroying all the files Dyson had kept, the original chip, and the body and chip of the new terminator. The terminator very clearly says that Dyson is just a few months away from finishing and releasing his new microprocessor, and he tells his wife that he’s “thiiis close” when we see him working at home.
If future events cannot be changed by time travel to the past, there is no way go reconcile the terminator’s dialog with the subsequent destruction of CyberDyne and Dyson’s files.
Alright, yeah. You’re right. We have to destroy the stuff at the lab, the files, disk drive… and everything I have here. Everything! I don’t care.
Sarah’s team destroys everything. Even working from an unmentioned backup, it’s implausible to think another team could have caught up with Dyson, completed his work, and released a chip within a few months. The terminator’s “detailed files” are clearly artifacts from a timeline incongruous with subsequent events. History changes.
The Past Can Be Changed, or, I Hope You Like Paradoxes
Moving away from the notion that the all events, past and present, are predetermined, is it possible that the future can be changed?
[Skynet] had no choice. Their defense grid was smashed. We’d won. Taking out Connor then would make no difference. Skynet had to wipe out his entire existence.
The Terminator had already gone through. Connor sent me to intercept and they blew the whole place.
Note Reese’s statement that “the Terminator had already gone through.” We don’t see this scene in the film, but from Reese’s lines there were clearly at least a few minutes between the time the terminator goes back and he does. During these few minutes, any number of things could have happened. The machines could have blown up their own time displacement equipment. They could have killed both Reese. The machine could have malfunctioned. Since we know that Fate doesn’t exist, we have to consider that all are possible future events, that none depend on another occurring in the future. When the terminator goes back through, the success or failure of its mission doesn’t depend on Reese going through a few minutes later. Indeed, since the terminator goes through first, and Reese isn’t already back in the past to stop it, there’s no reason to believe that the terminator wouldn’t succeed in killing Sarah at the Tech Noir club. The second the terminator disappears into the past with no one there to stop it, the world of 2029 should vanish, instantly replaced by a new world where John Connor was never born. History changes, the resistance isn’t led by Connor, it hasn’t defeated Skynet, and Reese isn’t there at the lab ready to go back in time to save John.
It gets worse. If John Connor is never born, the resistance never matures to the point that Skynet needs to resort to time travel. Even if they decide to do it on a whim, they don’t know about Connor, so they wouldn’t send back a machine to kill him. If they don’t send back an assassin, then he does get born (though not by Reese, who doesn’t have go go back after the terminator, despite that he can’t ever get back because it wipes out his timeline before he would have been able to go back), and he grows up to lead the resistance. Also if no machine goes back in time, no chip is available for Miles Dyson to study, so Skynet can’t be developed (at least not by him). If Skynet isn’t developed based on Cyberdyne technology, a reprogrammed terminator can’t go back in time to warn Sarah Connor about destroying the building.
So: paradoxes. It’s possible that the universe just doesn’t care about paradoxes, that they’re just problems our simple human brains and limited logic have. Maybe an effect can prevent its own cause and life can go on, but since I’m incapable of reasoning past my own reasoning capability, I’ll move on to part three.
Strings and Branes
String theory is a complicated physics thingie that uses terms like “strings” and “branes” to describe the structure of the universe that I’m not going to pretend to understand. Brian Austin Green says that the series’s time travel is based on it, so I’ll trust him on the matter.¹ Idea being: there is more than one layer to the universe. When one travels through time, one actually jumps from one’s own dimension to a new one. That new universe was identical to the previous one up to the point of arrival in the past. From there things will progress naturally and may diverge significantly from one’s original timeline. Using DC Comics’s parlance, I’ll call the original timeline “Earth-1” and the new world with its altered history “Earth-2”. “Earth-2” here is defined as the timeline anyone arrives on who travels in time from Earth-1.² When the terminator and Reese travel back to 1984, they’re really moving to a new timeline. Anything they do there will affect only that timeline’s future.³
Here’s what happens: The Earth-1 humans fight and defeat the machines. In desperation, a terminator goes back in time to kill Sarah Connor. Reese follows, leaving his dimension and arriving in the past of Earth-2. On Earth-2, Reese-1 saves Sarah-2’s life, falls in love with her, fathers John Connor, and dies destroying the terminator. Sarah retreats to Mexico, gets her picture taken by a small boy, and wonders what kind of world her son will grow up in. John-2 grows up, shows this photo to Reese-2, leads the resistance, wins, and sends Reese-2 back in time to save Sarah-3’s life. Earth-2 is the world of 2029 we see in Reese’s flashbacks, and Earth-3 is the world of the 1984 segments. We know it’s not Earth-2 because of the photograph. Sarah poses for this photo when she’s on the run in Mexico after having been warned of Judgment Day, and she’s started keeping a dog with her to help her watch out for terminators. The photo has to have been taken in a timeline when she already knows about the future. Reese-1 is from the original timeline where there was no time travel involved yet, so he couldn’t have seen that photo of Sarah.⁴
On Earth-3, Reese-2 saves Sarah-3, warns her of Judgment Day, and conceives John-3 with her. In 1995 a T-1000 and a reprogrammed terminator arrive from an unseen point on the timeline of Earth-2. The good terminator tells them about Miles Dyson, they blow up Cyberdyne, and either humanity is saved and John becomes a Senator or homeless drifter or whatever, or someone else invents Skynet, as the residents of Earth-1 did originally and as seen in Rise of the Machines and the Sarah Connor Chronicles, and the whole thing starts over again.
Timelines and Terminators and Branes, Oh My!
Judging from the previews, it looks like Terminator Salvation is going to deal more with time travel more directly than the other movies have. None of this time travel mechanics stuff is necessary to understand the first two movies, they just use it as the catalyst to start the action. The movies even tell you not to think too much about it, with Sarah line saying, “you can go crazy thinking about all this” and John’s that “it messes with your head.”
Personally, while the sci-fi string theory interpretation is necessary to allow for sequels, I actually prefer the notion that history can’t be changed and that they really are subject to the whims of fate. I like the inevitability that John knows he’s sending Kyle back to his death in the past, but that he has to go to become his father. I like the idea that the terminator brings about Skynet’s birth by getting killed in the past and leaving behind its technology for Cyberdyne to discover and bring about their own doom. Yes, it means Judgment Day is unavoidable, but it also means that John’s resistance ultimately wins.
- io9 sketches out the timelines from the TV series here. I’m providing my own take and won’t go into the TV series as much.
- I’m simplifying things somewhat by assuming that if two people leave Earth-1 they both arrive on the same Earth-2. You could imagine that one arrives on Earth-2 without the other second traveler, and then the second traveler arrives on an Earth-3 they both inhabit. This would allow for the Earth where the terminator arrives but Reese doesn’t. It’s moot, since to tell the story of the movie we just need the Earth where both arrive, so I’m not concerned with Earths we never see and don’t affect the story.
- Since all this happens in another dimension, the inhabitants of Earth-1 don’t really have to bother with it at all. They’ve already won their resistance. They could just shrug, say, “sucks to be Sarah-2”, and move on. Fortunately for the story they’re either too heroic for that or don’t understand sci-fi string theory.
- Earth-1 is a strange place; we never see it on film. This is the “first” timeline that hasn’t been fiddled with at all by time travelers. Kyle Reese isn’t the father of John Connor-1, since for him to be the father he’d have to have traveled back in time, which hasn’t happened yet. This John-1 must have been fathered by a unknown man, and he would have grown up without foreknowledge of Judgment Day. He wins the war against the machines without the benefit of a childhood being prepared by Sarah Connor, so he’s extra badass. Food for thought: is he better off than the others Johns? We know both get the job done, but by inadvertently changing half of John’s DNA Reese could have screwed things up badly. Also the Cyberdyne of Earth-1 didn’t already have a chip to base their invention on, so its Judgment Day was probably later than 1997. This is another reason we know the timeline of the movies can’t be Earth-2. If the terminator that comes back were from Earth-1, its J-Day would be different. If it gets picked up for a third season, I expect The Sarah Connor Chronicles to play with the idea of how John was affected by spending too much time trusting machines as a kid.