Why do they travel naked in time in Terminator universe? Is it ever explained in the movies or tv serials? If they cannot carry weapons, how do the cyborgs travel with metal under their skin?

  • 4
    :Glad you could finally post your question.
    – apoorv020
    Commented Jul 31, 2011 at 20:10
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    The real question is, "Why would Skynet invent a time machine that only works on living tissue?"
    – Jeff
    Commented Aug 1, 2011 at 21:15
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    And, of course, "Why not just grow skin over a nuke and send it back?"
    – Jeff
    Commented Aug 2, 2011 at 11:58
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    @pichoscosama - have you considered accepting an answer? Commented Aug 22, 2011 at 7:21
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    @TexasTubbs Why not nuke the site from... wait, wrong movie.
    – Mazura
    Commented Jul 24, 2015 at 5:13

5 Answers 5


Update - this has been bugging me for a while, I finally had to write it out. It's speculation (not taken from the scripts), but internally consistent with at least the first two movies.

In regards to Jeff's question, "why would Skynet invent a time machine that only works on living tissue" - I'm not convinced that a) Skynet did the inventing, or that b) it only works on living tissue.

First, we don't know that Skynet really invented time travel - even if one of the characters said Skynet did. It's entirely probable that some (human) laboratory had worked out the basic principles, but alas, never got a chance to publish their exciting results, prior to most of the human race being wiped out in a nuclear Armageddon.

Second, the Temporal Transfer Field doesn't only work on living tissue - see the T-1000 for a counter-example. In fact, the problem that Skynet encountered, was a lack of understanding of the principle of Chrono-topology.

Chrono-topology is the principle that the energy required to activate the Temporal Transfer Field, is correlated to the number of bundled timelines inside the Field 1 . One timeline exists for every object that had a separate existence through the past.

1: Note that power requirements appear to be 1.21 Gigawatts per timeline, making it prohibitive to send more than a single object.

For instance, a (naked) human has one timeline, as he exists as a unitary object going back in time. This includes his hair/fingernails, which are biologically dead tissue, because they are all in the same timeline. If the field only worked on purely living tissue, the subject's hair (and fingernails - ouch) would need to be removed.

If the subject human puts on a pair of jeans - now there are two timelines inside the field, as the jeans have their own existence and path back through the past. The same for picking up a gun (and the bullets).

The T-800s, having been created and (presumably) immediately had skin grown on, have a single timeline. Likewise for the T-1000s. If they were to pick up a weapon, that would double the number of timelines in the Field.

Why the increased energy requirements? The TTF, when activated, is basically trying to push an object out of its existing temporal path back in time, into a different path. The more distinct timelines, the more energy is required for the Field. A timeline is a four-dimensional path made by a physical object, travelling forward through time. Think of a bikepath through soft dirt, where the wheels have made a trench. If you ride a bike back down the trench, it takes an effort to force the wheels out of the trench.

Now, it is true that Skynet could do a number of things to circumvent this restriction, but see the next section for an explanation of why it doesn't.

Skynet is Pac-man on steroids.

Skynet is an AI, and doesn't process scenarios like a human. It follows certain rules programmed into it, no differently from one of the ghosts in Pac-man (just slightly more complex).

Two rules in particular, Local optimum, and Satisficing, prevent Skynet from doing more than the minimum planning necessary. First, when considering the sub-goal of how to send a cyborg through a time-field that seemed to only work on flesh-covered objects, Skynet would run through its list of available assets, realize that it already had flesh-covered cyborgs, and move to the next step - how to arm the newly-arrived Terminator.

For this second sub-goal, Skynet would realize that the Terminator could locally acquire weapons, sufficient to take out a waitress. Having satisfied both of its subgoals, Skynet would stop evaluating additional options, and carry out its plan. It has achieved a local optimum, and doesn't realize (or care) that there might be a better answer elsewhere.

Skynet, as an AI, just isn't creative, and doesn't seem programmed to make intuitive leaps, which would be obvious to a human. It processes trees of (known) options, and picks the ones that meet the given criteria.

Lucky for us...

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    +1 for a good discussion of AI and naive hill-climbing.
    – Jeff
    Commented Aug 2, 2011 at 11:58
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    But every atom in a living thing came from somewhere else. For mammals they mostly come from the food we eat. The atoms in the food came from other objects, and they... etc. So every object is made up of a huge number of previous sub-objects, and so previous timelines. It sounds good for sci-fi babble though!
    – Nick
    Commented Jun 29, 2012 at 14:57
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    Never clip your nails or cut your hair or lose some skin tissue though! That'd REALLY multiply timelines. I think it's about containment though. If it's all contained within the same membrane (the android skin) it only counts as one "unit". It also creates problems when androids get blown to bits btw. You could say Skynet fixed up some special anti-spreadoverlargeamountoftime matrial in the skin. And reg. not being creative, one super killer android really ought to be enough.
    – Lodewijk
    Commented Dec 17, 2013 at 22:57
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    I'll echo what Nick said - well-written answer, but I don't find it very convincing. Human tissue isn't a single piece of matter! Part of you comes from that burger you had last week, etc, and ultimately all matter comes from the Big Bang. So either this should always be a problem, or it should never be a problem. Furthermore I don't see anything here that gives movie-canonical evidence. Commented Apr 8, 2016 at 9:08
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    Why is this so upvoted? It lacks any evidenciary basis. I realize the standards in 2011 were different, but this error of history should be corrected. Commented Nov 27, 2017 at 18:38

I suspect it was deliberately kept vague to make a good story. But from the script:

SILBERMAN: Why didn't you bring any weapons? Something more advanced. Don't you have ray guns? Show me a piece of future technology

REESE: You go naked. Something about the field generated by a living organism. Nothing dead will go.

SILBERMAN: Okay. Okay. But this... cyborg...if it's metal...

REESE: Surrounded by living tissue.

SILBERMAN: Of course.

I think that's it for "official" explanations.

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    Based on that, it seems like the time machine must require the bioelectric field generated by a living body to target. Hey! I can BS better than some Sci-Fi writers!
    – Jeff
    Commented Aug 1, 2011 at 14:18
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    why don't they cover whatever they want to transport in the living tissue as well?
    – Sufendy
    Commented Aug 2, 2011 at 7:45
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    You mean the T-1000? That's a good question. I don't think it was ever directly addressed, but I could see two explanations. 1: The nanites composing its body may have been able to form into actual skin or 2: the t-1000 was sent back in time as a blob in a sheath of flesh, and then it immediately broke out of it.
    – Asmor
    Commented Aug 4, 2011 at 15:05
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    @WikisAtArea51 Indeed. I'd just chalk that up to a plot hole. E.g. There's no reason a gun couldn't just be encased within a terminator's exoskeleton, like Optimus Prime carrying the Matrix of Leadership in Transformers.
    – Asmor
    Commented Sep 23, 2011 at 20:15
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    For that matter, Reese could have brought back any advanced technology small enough to swallow. (Plot hole here, as it's out of character for future-Connor not to have thought of that.)
    – Tynam
    Commented Jan 4, 2012 at 11:09

I don't recall very clearly, but I think this issue was raised in the first movie. The guy sent back in time is being questioned about the terminator and he says that the terminator is surrounded by living tissue because bare metal can't be transported back, only living material can.

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    It was explained in the first movie... It was a scientifically horrible expliation why a complex machine like a gun could not be brought back, but a terminator could because of the living tissue surrounding it. I was like so feed the gun to a catfish and send them all back...
    – Chad
    Commented Aug 1, 2011 at 14:10
  • They only had these Androids on hand! All catfish died! Maybe swallow a teensy little railgunny though. Nah, no need, you're a terminator robot!
    – Lodewijk
    Commented Dec 17, 2013 at 22:59
  • The thing is, only Kyle Reese would need the advanced weaponry. The Terminator is chasing after a fragile human and (correctly) Skynet reasoned he could easily acquire a gun which could kill Sarah fairly effectively. It was Reese who needed the advanced weapons in order to fight the bulletproof terminator, but of course the humans probably don't have access to the "put a machine inside skin" technology.
    – komodosp
    Commented Nov 27, 2017 at 9:10

In some of the comic books, Terminators bring weapons with them back in time by storing them inside of dead humans.

  • In the one I read, it a live human. Not for long though; nasty way to go.
    – StuperUser
    Commented Apr 29, 2012 at 16:29
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    Yeah, should definitely be live humans.
    – Lodewijk
    Commented Dec 17, 2013 at 23:00
  • Nothing dead will go!
    – Mazura
    Commented Jul 24, 2015 at 4:57

The general argument posed in all such scenarios is that something about clothing is fundamentally difficult to transport at the same time as a person. One connected entity is easier to transport than multiple objects which are closely bound. It could mistake the distance, and thereby force clothing to stick to a person, for instance.

The Terminator wiki states:

The Terminator arrives nude because of the time machine being powered by organic matter, so that clothes, weapons, etc. can't be sent back.

  • What about the metal under their skins? Commented Jul 31, 2011 at 17:59
  • @pichoscosama: It seems likely that they must have created a metal specifically for the purpose of time traveling. Commented Jul 31, 2011 at 18:11
  • @pearsonartphoto: Why not make guns out of that metal?
    – DampeS8N
    Commented Aug 1, 2011 at 1:27
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    @Dampe - because then they couldn't have Arnie asking for Uzi 9mm Commented Aug 1, 2011 at 1:35
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    @pichoscosama: It's not a special metal (just the normal terminator endoskeleton), it's the flesh grown over it that lets them travel in time. Apparantly, T-1000 series robots can perfectly mimic that flesh, through SCIENCE!
    – Jeff
    Commented Aug 3, 2011 at 13:44

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