Mar 16 2008

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Bad Bad Movie Physics

Posted at 10:15 pm in Astronomy, Humor, Piece of mind, Science, Time Sink

I like the scifi blog io9, I really do. I read it every day, and I get a huge kick out of it (though avoiding the Doctor Who spoilers is tough).

But they had a post recently that kinda, well, blew it epically.

The topic was bad physics in movies. You might think that my calling them out on this is just due to insane jealousy on my part because they’re getting to be a popular blog and they didn’t link to my movie reviews even though I was among the first (if not the first, thankyavurrymuch) to review the science in movies on the web, and of course being an honest man I cannot necessarily dismiss that. Happily, though, my ego has the ability to charge on undeterred.

The io9 folks decided to rate several popular movies on how they treated various topics in physics, like faster-than-light (FTL) travel, communicating with aliens, sound in space, and so on. They did it like a check list, so if a movie abused a given topic, it got a check in that column.

Problem is, they got a whole lot of things wrong in their checklist! For example they only fault the Star Wars movies and The Last Starfighter for having FTL, when nearly every movie on their list has it.

So here is a more complete dissection of their list. Think of it as a check on the io9 checklist, sorted by movie:

1) 2001: They correctly said it didn’t have sounds in space, which is good, but then said it had a "weird depiction of exposure to vacuum". Weird? It was actually pretty accurate, and it’s rare to this day to have a movie treat this topic even close to correctly.

io9 than gave 2001 a check mark in the "people move in slow motion in zero gravity" category. I would say that’s a tough call; people in the movie move carefully in microgravity (a better term for it, though a lot of folks still use "zero-g"), not necessarily slowly. You don’t go zipping around in microgravity, you have to move a bit slowly to make sure you don’t launch yourself across the cabin.

Finally, they don’t rate 2001 as having FTL, but it does! In the end, when Dave Bowman takes The Ultimate Trip, he’s flying through the galaxy using wormholes or some such thing.

2) Contact: They don’t give it a check mark for FTL, when again that was in the movie. Actually, that was the whole purpose of The Machine, and was the whole point of the ending of the movie when Ellie has to present her science as if it were faith.

3) Armageddon: I am no fan of this movie (which is like saying black holes suck a little, or a supernova is a slightly energetic event), but io9 gave it a check under "Nearby asteroids aren’t drawn close by gravity". I was scratching my head over what that meant, but then saw a helpful description at the bottom of their post:

Asteroids or other objects shouldn’t be able to float close together without falling into each other’s gravity.

Well, that just raises further questions (for you Futurama geeks out there)! I’m not sure precisely what they mean by that, but gravity doesn’t works like a crane, reaching out and grabbing stuff and instantly moving it around. Also, and it pains me greatly to say it, as I recall Armageddon doesn’t mention the Earth’s gravity affecting the orbit of the asteroid; but just because they don’t mention it specifically in the script doesn’t mean you can give them a demerit.

4) Deep Impact: Once again, we get a check mark in that asteroid category. The only thing I can figure out for this in the movie is that the two chunks of the comet drift apart, and don’t fall back together. But the movie had it right! The two chunks separate after the detonation of a nuclear weapon under the surface of the original comet. Each of the two pieces of the comet are far too small to have enough gravity to pull significantly on the other. So they essentially orbit the Sun freely.

Did I miss something here? Any ideas from my BABloggees? I’d ask io9 in a comment but my account there doesn’t allowed me to leave comments.

5) Mission to Mars: They forget to note that there was FTL at the end of the movie; Gary Sinise’s character uses it to go to the alien homeworld. I would also give the movie a half-check under "Easy communication with aliens" topic, too.

6) Serenity: They give this one check marks under "All planets have Earth gravity" and "All planets have one climate world-wide". There is a narration at the beginning of the movie that specifically discusses terraforming, so you can’t fault the movie that. While we don’t have the tech now to terraform a planet, we know in principle it can be done. Firefly and Serenity both establish they have artificial gravity, though I suppose you can legitimately call them on that since there isn’t anything in well-established physics today that would allow that (though it’s impossible to say what will happen in the next few hundred years).

7) Stargate: io9 gave them no check for FTL. Um, what’s the title of this movie again?

8) "Alien" franchise: They give it a demerit for having interbreeding between aliens and humans. But that’s not really what was happening; humans were hosts, not contributing any DNA. Update: See the comments below the post; I concede that in the last two movies there was a limited form of interbreeding, kinda sorta. It was clear in the movies that the aliens were incredibly tough, resilient, and flexible for different environments. It’s not too much to ask that humans could be walking (well, sleeping) incubators for them. Also, the movies had FTL, which again went unchecked.

9) Enemy Mine: io9 didn’t have it checked under FTL.

10) They gave Apollo 13 a clean bill of health, which is true enough (though you’ll note the astronauts do in fact move slowly in microgravity), but the movie did have other (mostly trivial) accuracy errors, mostly due to combining different things from different Apollo missions for the sake of storytelling, which I’ll forgive (especially since it’s such an awesome movie).

11) They also gave The Right Stuff a clean bill of health, which is fine. My nitpick isn’t with the movie so much as with the book; the author made the astronauts look like posers, and the test pilots the real heroes. I object to that because it’s hugely unfair to the astronauts; both parties played their parts in history, and both showed incredible aptitude, bravery, and intelligence.


So there you go. As I learned long ago, nitpicking the science in movies is fun, and makes for a great blog entry, but in my opinion the io9 author in this case missed a lot of stuff, and was arbitrary about others.

I may have missed a few examples, too. The only movie on their list I’ve never seen is Solaris, so there might be something there too (I never saw Alien 4 either, having learned the franchise was dead and buried with Alien 3, but I assume there’s nothing there that wasn’t in the first three).

The hard part with all this, I’ve learned, is to know when a little snark is deserved and when it isn’t. I make mistakes too, even in my own areas of expertise, and sometimes I deserve a little teasing and sometimes it’s just an honest mistake. I don’t mean to be mean to io9, and had they made a few mistakes I wouldn’t bother commenting. I think the article would have been vastly improved with some details; specific examples from the movies to elucidate their points. They obviously spent a lot of time researching this (read: watching lots of movies), so that extra step wouldn’t have been too hard.

Again, I still love io9 and I won’t slow down drinking from their firehose of scifidom. There are lots of scifi blogs on the web, and even with this stumble io9 is among the best I’ve read.

151 Responses to “Bad Bad Movie Physics”

  1. Chrison 16 Mar 2008 at 10:32 pm

    I think they have not counted wormholes as FTL travel since they are ‘not traveling in our spacetime’.
    Also you would probably know better than me but would a comet (in Deep Impact) cause a massive wave? Would I not explode in the atmosphere ala Tunguska?

  2. noneon 16 Mar 2008 at 10:33 pm

    dear sir,

    wormholes =/= ftl

    that is all

  3. Jim Atkinson 16 Mar 2008 at 10:38 pm

    Re The Right Stuff- remember that it is written strongly from the viewpoint of a Yeager worshiper- Wolfe was greatly smitten with Chuck Yeager and a lot of the book reflects that. There are a few small technical errors and some complete BS in the film- NO civilians were on the flight line (excepting contractor personnel) and some of the planes are wrong, but seeing as how there aren’t any flying examples of some of them, they did the best they could (Cookout scene- that’s not a Douglas D-558-2, it’s a Hawker Hunter but only true geeks know that). The book is greatly superior to the movie- too much comedy relief (Shearer and Goldblum) and too much compression for plot purposes. Apollo 13 now- that’s a real movie. About the only gripe I have was some combination of actual personalities into one person for time saving.
    Now “From the Earth to the Moon”- that’s a REAL program. Tom Hanks should get Kennedy Center awarded just for that.

  4. Mitchellon 16 Mar 2008 at 10:45 pm

    FTL is ‘faster than light’, which implies that an object is accelerated to speeds beyond that of light. When things move via wormhole or warp drive, they are not accelerating beyond the speed of light. These methods of propulsion may not be any more practical, but at least they aren’t breaking that one rule of physics.

  5. Mark Martinon 16 Mar 2008 at 10:46 pm

    Interestingly, Apollo 13 *does* have sound in space. It also has some other sorts of physics errors. It definitely isn’t spotless.

    2001 also has several such technical gaffes, though not generally ones which are on the blog’s checklist.

  6. Saint Gasolineon 16 Mar 2008 at 10:48 pm

    Yeah, they shouldn’t have marked Aliens down for “interbreeding”. The aliens are parasitic on humans, not interbreeding with them, and even though most parasites tend to have very specific hosts, at least in principle a parasite with a vast array of generalized hosting options could arise. They actually have a life cycle that is very similar to certain parasitic wasps. I think they did a good job creating a sort of “super creature” that wasn’t totally unbelievable.

    Still, The Thing is creepier!

  7. Skepkidon 16 Mar 2008 at 10:50 pm

    In Alien 4, they did have a human/alien hybrid, it was made and implanted through genetic engineering( I think I never saw the beginning). It was supposed to be the ultimate weapon, then it killed the guy that created it ,the queen and Riley had to suck it out of a window into space, through a bullet hole.

  8. Crux Australison 16 Mar 2008 at 10:50 pm

    I read somewhere that the atmosphere on Mars is so tenuous that its strongest winds wouldn’t be able to knock a human over. Does that sound right? If so, that hurricane scene on Mission to Mars is even sillier than I thought.

  9. The Bad Astronomeron 16 Mar 2008 at 10:52 pm

    Nope. I’m not buying the “wormholes aren’t FTL” line. You get to a destination faster than light does, so it’s FTL by definition. It violates relativity.

  10. Juraon 16 Mar 2008 at 10:57 pm

    Actually Phil, the xenomorph in the “Alien” franchise were doing a bit of DNA swapping. This wasn’t really made prevalent until the last two films (the weakest, yet still orders of magnitude better than AvP). When the xenomorph host was a dog, the result was a different, yet decidedly familiar alien. When Ripley was brought back, one got to see a glimpse of some kind of DNA mixing between the species.

    What happens internally has never been fully described (probably best that way), but it is apparent from the films that the xenomorph do acquire some of their abilities from their hosts (which helps explains why facehuggers hold onto hosts for hours at a time, rather than a “pump and dump scenario. Have to find a way to make the two disparate “genomes” mesh).

    In terms of survival, it makes a deal of sense. Why bother evolving to best fit an environment when one can steal the necessary attributes from creatures that have already done so.

  11. autumnon 16 Mar 2008 at 10:58 pm

    When does the Alien franchise feature faster than light travel? The crews have to be hibernated, which implies long trips at sublight-speeds.
    If I have overlooked something, I apologize in advance (faster than light could ever apologize!).

  12. Shannonon 16 Mar 2008 at 10:59 pm

    “In Alien 4, they did have a human/alien hybrid, it was made and implanted through genetic engineering( I think I never saw the beginning).”

    In Alien 4, “Ripley” herself was a human/alien hybrid, leaning more towards the human, and created genetically. However, late in the film she seems to… uh… get it on somehow with the Alien queen. The queen subsequently gives birth to a full-blown human/alien baby. So… yeah. That check-mark is well earned.

  13. Mark Martinon 16 Mar 2008 at 11:00 pm

    I’m not sure I can agree with that. If a photon goes into the wormhole along with Dr. Arroway, that photon could easily beat her to the other end of the tunnel. She’s not traveling FTL locally.

  14. uknesvuinngon 16 Mar 2008 at 11:14 pm

    I’m not sure I even qualify as layman when it comes to physics, but isn’t the whole idea of travel through a wormhole is that it’s a shorter route than traveling to the same point through normal space? I’m not sure how that’s supposed to violate relativity. The object traveling through the wormhole never accelerates past or even the speed of light, it just travels a shortcut. I suppose you could still assume there was some FTL in Stargate implied by the fact that the two gates existed so far apart that the travel required to place them there would be an unfeasibly long period of time. I’m sad to say I’ve never seen enough of 2001 to say whether it has some example of FTL.

  15. Anneon 16 Mar 2008 at 11:15 pm

    The point is that the rules that “forbid” FTL forbid wormholes. They basically say “there’s no way to get from point A to point B faster than a photon going directly there”. Or rather, what they say is that doing that is the same thing as time travel. And indeed you can use wormholes to build a time machine: suppose you have two ends of a wormhole. Take one end and fly it around for a while at faster than the speed of light, and bring it back to next to the first one. Because of the twin paradox, the one that flew around will have “aged” less than the one that sat still, and so if you go into the one that sat still now, you come out of the one that flew around some time earlier. Bingo, time travel!

    What’s really disconcerting is that general relativity makes all this look disturbingly possible. The fundamental principle that forbids faster-than-light travel is just the idea that time travel should be impossible. Special relativity - which has been thoroughly and carefully tested - tells us that time travel and FTL travel are the same thing.

    P.S. for a description of wormholes used for FTL travel and time travel, see Robert L. Forward’s novel “Timemaster”. The writing is horrible - I mean really really bad, my head hurts just thinking about it - but the physics is sound (he includes a detailed list of references to peer-reviewed literature at the end).

  16. Rowsdoweron 16 Mar 2008 at 11:20 pm

    You might want to check out the Insulingly Stupid Movie Physics page at:

    http://intuitor.com/moviephysics/

    It’s got great stuff that covers more than just sci-fi, but all movie genres.

    As for Alien 3, yeah, it stunk. But that’s just the theatrical release. If you watch the director’s cut which is available in the Alien Quadrilogy set, you’ll see it’s a lot better than what you originally saw.

  17. Mark Hansenon 16 Mar 2008 at 11:25 pm

    In Alien 4 it was a problem with cloning Ripley that brought about the DNA mix. This was carried over into the queen which caused her to move on to a second stage of reproductive ability. How she became pregnant is anybody’s guess but it wasn’t Ripley getting it on with her. Maybe parthenogenesis, like Sea-Monkeys!
    I know, I know, it’s only sci-fi, it’s not real.

    Incidentally, there should have been a tick for “weird vacuum effects” for the Star Wars movies. General Grievous and his amazing cloak in Ep. III.

  18. Scorpiouson 16 Mar 2008 at 11:27 pm

    When FTL through an alien source, whether wormholes or some other FTL source, how can we know that it isn’t impossible? Maybe our human understanding of physics with regard to that isn’t to the point where we’d understand it.

    I say that due in part to the Stargates from the movie of the same name. On the TV series, it was found that a race of ancient beings created the Stargate system and them some went to a higher plane of existence, blah, blah, blah. Obviously, there we didn’t create it, so I guess I don’t see how we can be faulted for using something that was already made, working and in existence when we happened to stumble upon it. It would be like saying that a cave man couldn’t use a modern vehicle to go hunting in, even though he doesn’t know anything about it except how to use it.

  19. Mark Martinon 16 Mar 2008 at 11:33 pm

    Anne,

    The key to this is that SR is a limiting case of GR. SR is only strictly true locally, in spacetime of zero curvature. SR can be true locally even while GR accommodates much more exotic overall possibilities. A spatial element within a wormhole is still locally Lorentz invariant; there’s no FTL going on, and no violation of temporal orderliness.

  20. tacituson 16 Mar 2008 at 11:49 pm

    Curiously, the thing that most annoyed me about Armageddon wasn’t the shoddy physics/astronomy/science in general. No, what really had me almost leaping out of my seat and yelling at the screen was the stupid soppy farewell scene that dragged on for several minutes as the comet/asteroid/whatever was still bearing down on Earth.

    I mean, you have the life of six billion people depending on you detonating a bomb in time, and you decide to spend a few minutes (you don’t know you have) chatting to your mates? Right… That was by far the dumbest part of the already dumb movie.

  21. Mickon 17 Mar 2008 at 12:02 am

    “All planets have one climate world-wide”.

    This criticism of Serenity made no sense to me. In the movie all we really see of any planet or moon from the ground is wherever they happen to land the ship, so you’d only expect to see one climate.

  22. Chipon 17 Mar 2008 at 12:14 am

    Mark Martinon _
    “…A spatial element within a wormhole is still locally Lorentz invariant; there’s no FTL going on, and no violation of temporal orderliness.”

    Perhaps so, nevertheless as depicted, Dr. Arroway is transported past several locations within the Milky Way, many lightyears apart, eventually to arrive at an idyllic beach and meet her father, as he looked when she was a child; (both alien constructs to place her in a familiar setting and more effectively communicate.) Then she is returned to back to Earth without a noticeable temporal change or distortion.

    I don’t recall if Carl Sagan described any hint of the technical details for FTL travel in the book though he had several characters travel together and the builders in both the book and movie weren’t sure what the machine was really going to do. We could always speculate that it might be explained - in SciFi terms - by the “locally Lorentz invariant” existing within an envelope of “negative energy” or mini-universe which itself travels FTL relative to the outside universe. A wormhole could be hypothetically modeled so that specific points in space are reached by extreme bending of space itself, photons still travel at light speed locally in Dr. Arroway’s capsule, and the space outside is distorted, with photons still traveling at light speed there. But the distance she traveled seems FTL both her as well as to Earthly observers - if they could track her. A violation of relativity, not light speed, especially on her return trip.

  23. DaveSon 17 Mar 2008 at 12:42 am

    Well, gosh darn it, no. I’m going to take another whack at why wormhole travel isn’t FTL:

    The other side of the galaxy is something like 44 quadrillion miles away - it’s a number in the 10^17 range.

    If we left tomorrow, and traveled at the speed of light, the end of the journey would be almost as far in the future as the origin of human language is in the past.

    But the edge of the solar system (i.e., the outermost known planet) is at something like 3 billion - a number in the 10^9 range. IF (and this is the “Fi” part of “SciFi”) space neatly folds on itself 22

  24. DaveSon 17 Mar 2008 at 12:43 am

    (ooh - how did that get submitted???)

    IF… space neatly folds on itself 22

  25. DaveSon 17 Mar 2008 at 12:57 am

    (ooh - how did that get submitted???)

    IF… space neatly folds on itself 22 quadrillion miles out, and a point from there is bent to meet a point somewhere in the 18 quintillion square miles of the solar system, the time it would take at speeds we’ve already achieved changes from “all of it” to a lifetime, give or take.

    That doesn’t mean that movie-style hops from one wormhole to the next are within our grasp - you can’t yet buy a map for the wormholes of the stars tour - and it certainly violates some pretty big concepts of how the universe works with its selective space bending, but still, wormhole travel changes the picture from one that blatantly ignores the laws of physics to one that requires a few implausible jumps. It’s still possible that space can effectively fold on itself, but short of discovering a wormhole (and waiting “only” 75,000 years for a proof that would otherwise take 150,000), we can’t quite prove that it’s IMpossible.

    (If it weren’t for the oops submission, I probably wouldn’t have posted anything on this - I write a lot of comments meant only for myself, just for the exercise of writing them.)

  26. Walabioon 17 Mar 2008 at 1:05 am

    AlienFacts:

    No Faster-Than-Light-Travel

    Alien/Human-Hybrid:

    In the Alien # 3, Ellen Ripley had a queen growing in her. She committed suicide so that it would not mature by throwing herself into molten lead. The Corporation, AKA Haliburton.Com, which runs everything did not let that stop it. The Corporation gathered genetic material. The genetic material was:

    * - Badly degraded.

    * - crosscontanimated.

    In Alien # 4, the Corporation of first 3 films collapsed, but the new government picked up where it left off. The military, through reconstruction and separation, could finally grow clones of Ellen Ripley and the alienqueen. The aliens had some human DNA and the Ripleys — all 6 of them — had alien DNA.

    The queen laid eggs which hatched into facesuckers, which planted embryos, which grew into aliens. The queen also birthed a human/alien-hybrid.

    In Alien # 4, the Ellen Ripley we see is throughout the movie is Ellen Ripley # 6. We get to see the first 5 in the Laboratory Of Horrors:

    In the Laboratory of Horrors are 4 dead grotesque Ellen Ripleys preserved. They are grotesque deformed chimeras with human/alien-characteristics. Ellen Ripley # 5 was still alive. She was a horrendously deformed chimera in pain begging for death.

  27. Kenon 17 Mar 2008 at 1:17 am

    I’m so glad B.A is touching on this again. As someone who became a reader of this site because of those articles I’d love to see B.A do some more.

    I don’t even wanna think on the FTL thing. Everytime I do I start trying to piece together “The Forever War” in my head again and I end up confused. They can go through a womrhole-like thing and it is apparently instant, but they still lose time. Its too big for me, I grasp it, I lose it, I grasp it again.. damn wormholes!

  28. Crayshon 17 Mar 2008 at 1:42 am

    Jura is partially right about the Aliens.
    They do draw a bit of DNA from their hosts, as seen in AvP:R When it “bred” with an alien and had an obviously different look to it.

  29. Crayshon 17 Mar 2008 at 1:43 am

    Er I mean when it bred with a predator

  30. Walabioon 17 Mar 2008 at 1:50 am

    I love FireFly it has the best physics of any TV-show, but in the push to get the episodes done, one episode had errors:

    All of the episodes are error-free except Episode # 01:06 (Season # 1, Episode # 6) Our Mrs. Reynolds. That episode has three errors:

    * - The net should not generate visible coronal discharge in space.

    * - The Serenity, being a big Faraday-cage, should protect itself and its crew.

    * - Vera should work in a vacuum.

    I like to solve these problems thus:

    * - The net fire ions. This builds a thin atmosphere around the net through which one see the electrical discharges.

    * - The ions, when they hit the metallic hull, create mesons which irradiate the crew.

    * - Jayne Cobb is an idiot and everyone was under too much stress to realize that he is wrong.

    The last point is the hardest to believe because Jayne Cobb is not that dumb and Zoe Alleyne Washburne and Malcolm Reynolds are not only combat-veterans but also military officers.

    All series have to have at least 1 episode which is not properly polished. No one is perfect.

  31. DaveGon 17 Mar 2008 at 2:03 am

    @autumn - the Alien franchise needed both hibernation and FTL. They talk of star systems in Alien 1. And in the Alien 2 movie after they get stranded the question of how long after they are overdue can they expect help comes up. The answer is several weeks. So even if the planet is orbiting our nearest neighbour that’s FTL.

  32. Reedon 17 Mar 2008 at 2:35 am

    FWIW, the long duration ISS crews zip around fairly quickly inside the station, despite the fact that it is jam packed with delicate equipment and hard edges. New arrivals move more slowly. EVAs are done at a much more deliberate pace, in part due to the stiff and bulky suits.

    You can see all this on NASA TV.

    I don’t recall exactly how the movies in question portrayed this, but you can’t really fault them for not being completely accurate. Maybe when bigelow gets his stations going, we’ll see some filmed with the real thing.

  33. Hakobuson 17 Mar 2008 at 2:37 am

    Dear Xenu how many people don’t know what they’re talking about (though I’m glad some do). Here are a few points:

    1) Wormholes =/= FTL. A wormhole is a shortcut from A to B, but there is no FTL going on. End of story. Someone commented that the “rules” that forbid FTL forbid wormholes, which just isn’t true. They also said to build a timemachine you need to fly around one end of a wormhole at FTL speeds, which also isn’t true. You only need to move it around, the faster you move it in relation to the end that stays “still”, the bigger the time difference becomes. No need to move FTL, though the closer to C you move it at, the “quicker” the time difference becomes significant.

    2) Alien 4 had Ripley having a sort of sex with the alien queen. Which produced offspring. If you haven’t actually seen the films in question, please don’t comment on them.

  34. Timon 17 Mar 2008 at 2:52 am

    About 2001:

    A lot has been said about this ending, but one interpretation is that there actually is NOT FTL at the end, but that he just goes completely, completely insane there, and that it is all in his head, being planted in there maybe.

  35. Pieter Kokon 17 Mar 2008 at 2:56 am

    Phil argues:

    Nope. I’m not buying the “wormholes aren’t FTL” line. You get to a destination faster than light does, so it’s FTL by definition. It violates relativity.

    Oops… wormholes are relativity! The point of the checklist, as I understand it, is to mark down movies for physical impossibilities. FTL as it is normally understood is such an impossibility. However, right now there is no physical law that says you can’t travel via wormholes (but the mileage of such vehecles is another matter altogether).

    I think you have to concede this one, BA.

    Also, Anne: the twin paradox is not time travel, it is the phenomenon of ageing at different rates due to movement. For time travel you typically require that the twin can go back to the moment he was the same age as his brother. Otherwise Walt Disney is doing time travel right now…

  36. Brett Garsedon 17 Mar 2008 at 3:06 am

    I read your blog regularly and really enjoy your movie reviews! I wish you had more time to devote to this as it’s a great way for people like me to learn something. Stick to your guns and remember that a lot for a lot of people Bad Astronomy is #1.
    Cheers,
    Brett.

  37. StuartVOon 17 Mar 2008 at 3:17 am

    Is the concept of “wormholes” based on even remotely-solid physics? Or are they just an item on the “wish-list” of sci-fi fans?

    I don’t know the answer myself. It may be that everyone here but me knows of some special cases of GR that do permit wormholes.

    Anyway, the answer to this question would have a lot of bearing on the issue of whether “wormholes” are any more “scientific” than “hyperspace” or any other pseudoscience commonly used to violate SR.

  38. Pieter Kokon 17 Mar 2008 at 3:26 am

    Here is the original paper suggesting (time) travel using wormholes. It is a good starting point for a literature search. Also check out the work by David Deutsch.

  39. Mooseon 17 Mar 2008 at 3:28 am

    Aliens franchise: AvP established (although as I understand it, this was established in the comics) that Xenomorphs grown in Predators have different jaws than Xenomorphs grown in Humans. Pause the film and take a close look at the Xenomorph-ling in the last scene.

    The book (IIRC) establishes that Xenomorphs have the ability to adapt fairly drastically to their host species, and are thus able to reproduce with/in a very wide variety of host species.

    On that basis, I think the checkmark isn’t completely invalid.

  40. codegirl.dkon 17 Mar 2008 at 3:37 am

    @Badastronomer: as others have said, going through a wormhole is not faster than light travel. Let me illustrate this with an example: you are driving from point A to point B. There are two ways to get there, one where you have to travel 100 km (i.e. the scenic route), one where you have to travel 50 km (i.e. a shortcut). You are moving at 50 km/h. The scenic route takes 2 hours, and the shourcut takes 1 hour.

    Now say you don’t know about the shortcut and make the erronous assumption that it always takes 2 hours to travel from A to B (because going more than 50 km/h is illegal). If you then notice that someone else, who took the shortcut, has traveled from A to B in one hour, you do _not_ conclude that the one traveling the shortcut traveled at a speed of 100 km/hour and gets a speeding ticket. That is essentially what you are doing if you are saying that going through a wormhole is FTL travel.

  41. Spankermaticon 17 Mar 2008 at 4:14 am

    @Hakobus - “Alien 4 had Ripley having a sort of sex with the alien queen. Which produced offspring. If you haven’t actually seen the films in question, please don’t comment on them.” ????

    Physician heal thyself. As was stated earlier, Ripley was cloned several times by the military scientists in the space station. She never had any weird or kinky sex with aliens. They were trying to clone her to get the Queen DNA, which if you remember the 3rd movie, was inside her at the penal colony. She even says it -”its a queen”.
    They did the cloning, but they ended up with several dud Ripley’s (which she finds and shows the business end of a flame thrower to) and the Alien Queen herself which although lays some eggs, also has a live birth of the weird alien baby due to DNA scrambling of some kind.

    Although not a fan of the 4th movie, I am still a massive fan of the Alien franchise. Best you re-watch all of them again to familiarize yourself with the plot.

    BTW - Phil, I agree with JURA. The DNA swapping is explained in several of the graphic novels and the extra bits on the DVD’s. In the 3rd movie, it was supposed to be an ox, not a dog as the host, to explain some of the more bullish aspects of the creatures design. but that was cut from the theatrical release.

  42. DaveGon 17 Mar 2008 at 5:12 am

    On the FTL wormhole thing. It sounds to me like there isn’t enough granularity and clarity in io9’s rating. If they were thinking internal FTL (ie. ship mounted) then that would explain their choices. Contact, Stargate, and 2001 were were all external FTL.

    Also, even allowing for corrections to the list, there isn’t a good correlation between good (or enjoyable) movies and good (or bad physics). Some of these movies violated physics a lot and were still enjoyable, others didn’t violate physics much and stunk.

    A lot of that may go back to when and how exactly you’re asked to suspend your disbelief. Roddenberry used a test that was used to weed out stupid scenes - the example was something like would the Captain really kiss the girl in the midst of a battle. Yes Kirk issed the girls. Even once on the bridge. But not in battle.

    It would be interesting to see these movies weighed on other factors like plot elements, stupid scenes, etc.

    Additionally, a lot of bad movies that play loose with science are guilty of grossly exaggerating things. Things like, mounting a never before done space mission in a few days, or having people and machinery quick freezing in seconds super storms. It’s not enough for you to suspend your disbelief and see where the plot takes you. They continuously ask you to bend or break your disbelief when there should be no reason to.

    There were lots of movies that could find a good blend. Anyone remember Marooned from the 70’s? No sound in space. Rescue mission to space based on available off the shelf components.

    Some aspiring consultant could draw up a 2×2 matrix, showing physics violations against credibility violations :)

  43. Nigel Depledgeon 17 Mar 2008 at 6:17 am

    Scorpious said:
    “When FTL through an alien source, whether wormholes or some other FTL source, how can we know that it isn’t impossible? Maybe our human understanding of physics with regard to that isn’t to the point where we’d understand it.”

    The thing about FTL travel is not that we are incapable of making a machine that can do it, but that it is prohibited by special relativity. Special relativity has been extensively tested, so we know that, even if it is wrong, it is a good approximation. Thus, even if our present understanding of physics is wrong, FTL travel is highly likely to be genuinely impossible.

  44. Tom Kon 17 Mar 2008 at 6:23 am

    It might be interesting to see a rating chart of movie physics accuracy, something like a scale of 0-100 with Armageddon rating a 5 (at least they wear space suits) and 2001 about a 97. Where would other sci-fi movies land on that scale?

  45. DaveGon 17 Mar 2008 at 6:53 am

    Of course if your going just for physics violations ….. how about all those flicks where a bullet impact throws people across the room, shooting through structural elements, seeking protection from machine gun fire behind car doors, ….

  46. Tom Kon 17 Mar 2008 at 7:09 am

    I’ve seen it stated (and attributed to Clarke) that the only physics they got wrong in 2001 was that when Dr. Floyd is sucking food through straws during his trip to the moon, the fluid goes down in the straw when he stops. I don’t think that’s necessarily a flaw - if the goop is sealed in a bag in each container (so that there’s no extra air) the bag might tend to resume its shape and pull the food back down the straw.

    I see two other small flaws and one large one. First, when Dr. Floyd arrives at the moon they have a meeting in a conference room. Everyone moves in the room as if they’re still in full Earth gravity, rather than bouncing along with a 5/6 lighter step when they walk. They get this more correct later on when they are in spacesuits at the monolith, moving slowly and carefully to simulate the reduced gravity.

    Second (and this isn’t really an error per se), the moon shuttle that takes Dr. Floyd from Clavius Base to the monolith site is shown gliding a constant height over the moon’s surface. This would only be possible if the shuttle were creating a constant downward thrust that exactly matched the vehicle’s weight. Interestingly, to maintain a constant forward motion they would need to apply a rearward thrust only at the beginning of the journey - with no air resistance to overcome (and assuming the downward thrust is perfectly aligned) the vehicle would continue to glide forward like an air hockey puck. An equal thrust from the front to stop it would be needed at the end of the trip. The unlikelihood of this approach rests on the fact that the shuttle would need to be applying downward thrust continuously throughout the entire journey. Not impossible, but unlikely.

    A much more efficient approach to traveling any appreciable distance on the moon would be a simple ballistic arc. Take off straight up and immediately after clearing the ground, orient the vehicle to the required bearing and attitude. Thrust for a calculated amount of time and then cut the engine. The vehicle will continue on its ballistic arc like any projectile. During the flight, thrusters would adjust the craft’s attitude so that as they approach the landing site the main engine will be pointed opposite the direction of movement. At the appropriate moment, the main engine is restarted and slows the vehicle to a landing in a mirror image of the takeoff.

    The third error (and really the only Major one in the film) occurs when Dave is in the pod, moving out away from Discovery to retrieve Frank’s body. A number of shots are shown from Dave’s point of view looking out the front window, showing the stars moving horizontally across the field of view. In fact, the stars should be stationary as the pod is moving in a straight line - the stars would be perceived as moving across the field of view only if the pod were rotating about its vertical axis. Of course this is done only to impart a sense of motion to the scene, much like the “whoosh” as the Enterprise flys by in the opening credits of Star Trek. If it were done correctly it would look as if the pod wasn’t moving at all. Frank’s body would simply get larger and larger in the window as the pod approached him, with the stars stationary in the background. (Dave might not even be able to see the stars at all, depending on the level of lighting within the pod.)

    I haven’t seen this flaw mentioned anywhere else whenever 2001 is discussed (although I haven’t exactly researched it thoroughly) but it’s so obvious when you realize it that the scene becomes irritating to watch. I almost get dizzy because I know the pod should be rotating to make the stars move like that.

  47. Brownon 17 Mar 2008 at 7:13 am

    As long as we’re grumbling, my beef is with Phil’s assertion that the book The Right Stuff “made the astronauts look like posers.” It’s fair to say that there was some concern that the astronauts FELT like posers. They felt more like lab rats and passengers than like real honest-to-gooodness pilots. But one of the charming things in the story is that the astronauts changed the paradigm, so that they could really be pilots.

    Make no mistake, the final astronaut to fly in the Mercury program, Gordon Cooper, piloted his craft. His automatic navigation systems failing, Gordo lined up his craft for reentry manually… and came down closer to the carrier than any other astronaut!

    Scott Carpenter, who was treated as something of a goat after his mission (he used his fuel unwisely and overshot his splashdown area badly, leading some to think he may have died on reentry), is treated by the book in a surprisingly heroic fashion. Carpenter had a lot to do in space, and he tried to do as much as he could. (Other astronauts groused about having to do in-space experiments, but Carpenter thought they were kewl.) Sure, he overshot his splashdown area, but it was no big deal; he’d simply have to wait a little longer to get picked up. Carpenter was enthused by how much he’d been able to accomplish in space, but his accomplishments were largely forgotten. Rumors circulated that Carpenter had lost his head during the flight. The rumors were false, but the damage to Carpenter’s reputation was done. He never flew in space again.

    Even Deke Slayton, the only member of the Mercury seven not to fly in Mercury (he eventually made it into space in the Apollo-Soyuz mission), was most certainly not a poser. Slayton had atrial fibrillation, which had never been debilitating, but the flight surgeons grounded him anyway. The other astronauts decided to make Deke the “chief” astronaut, which everyone else assumed was a cosmetic position. Deke thought otherwise. He took charge and helped make the space program truly great. No lab rat, he.

  48. Charleson 17 Mar 2008 at 7:15 am

    On Serenity, the characters go to one part of a world and don’t explore the whole planet. I guess they are supposed to have different climates every time they cross the street or go 20 miles?

  49. Brownon 17 Mar 2008 at 7:18 am

    Another 2001 flaw: Watch the space station. It rotates in one direction (say, clockwise), then suddenly is seen rotating in the other direction (counter-clockwise). Check it out!

  50. Barton Paul Levensonon 17 Mar 2008 at 7:46 am

    The remarks on human-alien interbreeding in the Alien franchise refers to Alien Resurrection (movie #4), where a military bioengineering lab was trying to combine alien and human genomes. Apparently both species have DNA, which I for one find a little hard to believe. The number of possible biochemicals is, well, astronomical.

  51. Barton Paul Levensonon 17 Mar 2008 at 7:48 am

    BA, wormholes don’t violate relativity. They are posited and worked out using the math of general relativity. They only violate an absolute interpretation of one rule in special relativity, which is an approximation that, in the case under discussion, doesn’t apply. See if you can find Miguel Alcubierre’s 1994 paper in Classical and Quantum Gravity for an example of how to do this stuff. Something can move faster than light globally without doing so locally.

  52. zandperlon 17 Mar 2008 at 7:49 am

    I agree that wormholes aren’t FTL. The definition of speed requires distance traveled. The distance you travel through a wormhole is significantly less than the distance in normal space. Therefore you are traveling a short distance in a certain time, so you have a low speed. QED.

    Now, the object’s ~velocity~ might be high, since displacement is used for the definition of velocity, but not its speed, and speed is what is relevant in the phrase FTL.

  53. Kevinon 17 Mar 2008 at 7:53 am

    One error in 2001 I noticed after years of worship of the film: when Bowman is outside trying to save Poole, the stars in the background twinkle. Oops! :)

    And how dare someone say something bad about Serenity! Phil, when you get to DragonCon, tell Adam Baldwin to go Jayne on their collective behinds! :)

  54. Barton Paul Levensonon 17 Mar 2008 at 7:56 am

    Hakobus writes:

    [[Alien 4 had Ripley having a sort of sex with the alien queen. Which produced offspring. If you haven’t actually seen the films in question, please don’t comment on them.]]

    I have seen the films in question, and I have seen Alien 4 several times, and Ripley is never shown having sex with the alien queen. She’s shown semiconscious in a big writing mass of aliens, but there’s no reason to think that that’s “having sex” with her, or with them. And in most cases, two girls having sex can’t have kids. The kid was produced because the military bioengineers had been doing weird things to their captive queen, giving her a human-style reproductive system in addition to her normal egg-laying system.

  55. Barton Paul Levensonon 17 Mar 2008 at 8:05 am

    Time travel is also compatible with general relativity. These are the major papers on the subject, in temporal order:

    Lanczos, Kornel 1997 (1924). “On a Stationary Cosmology in the Sense of Einstein’s Theory of Gravitation”. General Relativity and Gravitation 29, 363-399.

    van Stockum, Willem Jacob 1936. “The Gravitational Field of a Distribution of Particles Rotating about an Axis of Symmetry.” Proceedings of the Royal Society of Edinburgh 57, 135-154.

    Tipler, Frank J. 1974. “Rotating Cylinders and the Possibility of Global Causality Violation.” Physical Review D 9, 2203-2206.

    Morris, Michael S.; Thorne, Kip S.; and Yurtsever, Ulvi 1988. “Wormholes, Time Machines, and the Weak Energy Condition.” Physical Review Letters 61, 1446-1449.

  56. Carlon 17 Mar 2008 at 8:09 am

    Phil, I love the blog but I’m afraid you’re mixed up on the FTL. Wormholes don’t violate General Relativity, even though creating one would provide a path to time travel, and keeping one stable does require some exotic (not to mention speculative) physics. Ask Kip Thorne the next time you see him.

    In fact, Relativity as a whole doesn’t rule out time travel. It does tell us that getting somewhere faster than a photon would can lead to time travel, but it doesn’t forbid that, it just warns us of the consequences. In fact there are several possible ways to create such situations; one of the earliest examples was Godel’s solution to GR for a rotating universe.

    Because time travel has such disturbing implications for causality, some physicists, most notably Hawking, have speculated that some as-yet unknown principle will be found to forbid it in practice — but GR certainly doesn’t.

    For a good lay overview of wormholes and other superluminal loopholes that don’t violate GR, see “Faster Than Light” by Nick Herbert.

  57. Rob Knopon 17 Mar 2008 at 8:14 am

    Re: wormholes and warp drives. Hartle’s undergraduate General Relativity text does in fact have a “warp drive” metric. However, to realize the curved spacetime provided by that metric, you’d need a *negative* energy density, and not only is that something unknown to modern physics, it’s not even really clear to me exactly what that means…. (Negative pressure I’m down with, mostly, and we’ve observed stuff out there that’s got it. But negative energy density? Huh.)

    I think the same may be true of wormholes. There are wormhole metrics in GR, and indeed in quantum gravity they’re probably opening and closing all the time. However, the most natural wormhole metrics are not *static*. The wormhole opens and closes fast enough that you would have to travel faster than light (even locally, where SR applies) to get through it.

    Re: Contact and wormholes, years ago when I was at Caltech, I heard a few talks from Kip Thorn about wormholes. The story he tells is that Carl Sagan called him up and asked him the question: could an arbitrarily advanced civilization construct and maintain a traversable wormhole? The idea is not to worry about engineering “details”, but just physical possibility. This led to a multi-year research project pursued by both himself and Stephen Hawking, where they debated the issue. I heard one talk that Hawking gave when visiting Caltech where the two got into a sort of argument about it at the end. As I remember it, the finally conclusion of all of that was that maintaining the open mouth of the wormhole would require a divergent energy density, so that even if the wormhole could be maintained, nobody in principle would survive entering it. I may be remembering wrong, however, and it’s been more than a decade.

  58. sandmanon 17 Mar 2008 at 8:23 am

    One thing he missed on Armageddon. The shuttles fly in formation like airplanes even in the absence of air.

  59. Ginger Yellowon 17 Mar 2008 at 8:35 am

    The worst movie physics I know is The Core. You can’t go two minutes without screaming: “That’s just not possible!”

    The worst physics in Star Wars comes in the most recent one, when some attack droids get blown off Obi-Wan’s ship by wind resistance. In space.

  60. Mark Martinon 17 Mar 2008 at 8:50 am

    The rationale for all the aerodynamics in Episode III (provided belatedly, in the DVD commentary) is that the battle takes place in Coruscant’s upper atmosphere.

  61. gopher65on 17 Mar 2008 at 8:55 am

    See… the problem here is that if you say “wormholes aren’t FTL”, then nothing is. I’ve never seen a scifi show or movie that had actual FTL in normal space, with the exception of BSG1978. Everything else has something like “warping space” (Star Trek), “extra dimensional wormholes” (Stargate), or “Hyperspace” (too many to count).

    So are none of those things FTL? Cause it sure as heck seems that to me like they are moving faster than light in Star Trek. Don’t you think?

    FTL means “moving from point A to point B faster than would be possible for a photon moving through normal space.” Any other definition is ludicrous and meaningless due to the number of exceptions and special exemptions. FTL does not mean “faster than light travel that must violate special relativity”.

    And, once again, on the off chance that someone will answer me, I’ve done google searches on this, but I still can’t figure out how to do quotes in a Wordpress comment section. A little help here please :)?

  62. Mark Martinon 17 Mar 2008 at 8:59 am

    Rob Knop brings up the real crux of the wormhole problem. Wormholes are consistent with GR’s formality. But they are also generated by granting a hypothetical element, negative energy. It’s the same with the Alcubierre drive. Wormholes can be rigorously studied in theory, but may be non-physical solutions to the GR field equations.

  63. Torbjörn Larsson, OMon 17 Mar 2008 at 9:20 am

    But that’s not really what was happening; humans were hosts, not contributing any DNA.

    But that’s not really what was happening either. In Alien #4 scientists try to separate tissue samples from before the death of Ripley and her implanted alien from #3. IIRC they directly refer to genetics - but in any case they show a lot of “hybrids” with mixed development, indicating not cellular but genetic mix, and more reflective of the probable success of cloning single cells.

    The final Ripley clone has weak access to Ripley’s memories through the aliens genetic memory inheritance mechanism [and that’s another check mark, btw], as well as enhanced strength, durability and organic acids in her blood stream.

    Likewise, the queen clone that starts out in classic fashion with an insectile breeding system and regular alien eggs and workers, eventually develops a mammalian type breeding system before delivering a mammalian/alien hybrid from her mix of genetic properties. The movie makers wanted a more likable yet scarier monster to kill.

    I think they have not counted wormholes as FTL travel since they are ‘not traveling in our spacetime’.

    But they, like other global solutions to GR, create timelike closed loops which AFAIU admits time machines. There are a lot of reasons to think this doesn’t work, beyond unrealistic requirements for energy or exotic matter. (IIRC the Alcubierre type warp drives violate all sorts of energy conditions - so maybe it isn’t a bona fide GR solution.)

    One weak way of reasoning is the question “where are the time travelers”? A stronger is to object to the time machine destruction of the Church-Turing thesis as it is promoted to a physical principle along the lines of computer scientist Scott Aaronsson proposed constraints for physics. If nature could solve NP-complete problems efficiently, say by wormholes, physics and CS as we know it wouldn’t exist.

  64. Torbjörn Larsson, OMon 17 Mar 2008 at 9:25 am

    But they are also generated by granting a hypothetical element, negative energy. It’s the same with the Alcubierre drive.

    Oops, sorry, missed that and Rob’s comment. Glad to see I’m not totally out of this universe on this (I haven’t studied GR, in case it wasn’t obvious) - that would mean entirely too much negative energy for me.

  65. Donnie B.on 17 Mar 2008 at 9:33 am

    I think the reason Serenity got tagged is not that a single world failed to have multiple climates, but that multiple worlds all had more or less the same climate.

    Lilac (where they pulled the “bank job”), the mining colony, and the world near the end of the movie whose name I won’t mention because it would be a spoiler, all had climates and ecologies that were remarkably similar to Southern California. (Imagine that!)

    Now, you can fanwank this easily enough. Maybe the engineers that designed the terraforming machines were inordinately fond of the Los Angeles area of Earth-That-Was. Still, considering the fact that the various planets were at varying distances from the new system’s sun, the job of making them all so similar would be tricky at best.

  66. Donnie B.on 17 Mar 2008 at 9:39 am

    Walabio, I won’t comment on your first two points. Regarding the third, I prefer to think that Vera has an interlock to prevent her firing in a vacuum for safety reasons.

    I agree that it’s implausible that Jayne would be wrong about Vera’s characteristics. If there was one thing Jayne knew well, it was his weapon. Er, I mean, weapons.

  67. Pieter Kokon 17 Mar 2008 at 10:00 am

    Rob Knop and Mark Martin: Negative energy density in the stress-momentum tensor is what causes the Casimir force. Or you can consider the reverse: the Casimir force “creates” negative energy density. So it is known in quantum physics, but in order to produce enough of the stuff to open up a wormhole wide enough you need a lot of energy, as you mention.

    gopher65: There are papers out there on the physics of warp drives. Again, you need a lot of energy for this, since it also requires negative energy densities. In any case, if you do not travel through space, but rather bend space, the definition of velocity as the distance travelled in a period of time is meaningless, because the space ship is technically always at rest. At no point is there any acceleration. There are still plenty of straight FTL drives in SciFi, though, such as the Millenium Falcon.

    PS. For quote tags, type “blockquote” in angular brackets, and include a forward slash in the closing tag, just as in regular HTML closing tags.

  68. Earl's TVon 17 Mar 2008 at 10:05 am

    As Pieter said, wormholes *are* relativity. Claiming that travel via wormhole is FTL is like claiming that a ship passing through the Panama Canal is traveling faster than 2200 mph. Furthermore, why pick on FTL? I think FTL (or wormhole travel) or even time travel has better grounding in physics than artificial gravity (angular acceleration notwithstanding), anti-gravity, or matter transporters.

    I was mostly disappointed with what wasn’t on the list, like:

    * Non-Newtonian maneuvers in space. Nothing irks me more than this. Lucas said he intentionally used aerobatic motion in space because he couldn’t make Newtonian motion exciting. Baloney. I defy you to find a physics nerd who didn’t get a woody the first time he saw a Starfury on Babylon5 executing Newtonian maneuvers in space.

    * Incorporating multiple theories. For instance, is the past inviolate, or are there different time lines? Pick one. Don’t use whichever is convient to advance the plot and then change it for the big ending.

    * Planetary nebulae are glowing fog banks. BA covered this not too long ago. Suffice to say that, despite the pretty vortices Voyager leaves in its nebula wake, you’d actually have a difficult time detecting whether you’re in the middle of a nebula.

    * 30 mph light-based weapons. I know this is just the flip side of the “dodging light-based weapons” coin, but if the Death Laser is depicted as emanating from the weapon’s barrel at sub-highway speed, then being able to dodge it is only a symptom of the underlying problem. (This is another thing B5 had the courage to get right.)

    There are more, but I gotta go now…

  69. Ianon 17 Mar 2008 at 10:13 am

    Looking at their list, the rule that “people shouldn’t be able to dodge lasers and other speed-of-light weapons” also seems contrived. I don’t recall any of the specific scenes they’re calling out, but in principle it should be possible. The hero may not be able to see the beam headed at him in time to dodge, but he can observe that somebody is pointing a weapon at him and try to get out of the way before the trigger is pulled.

    Another way of looking at it: is dodging a laser any less realistic than dodging a bullet from a conventional gun? Either way, the projectile moves much faster than you, and if you haven’t gotten out of the way by the time it’s been fired, you’re going to get hit.

    Now, if it were Neo dodging lasers the way he dodges bullets, I might have a problem with that. Then again, maybe special relativity just doesn’t always hold in the Matrix.

  70. Thomas Sieferton 17 Mar 2008 at 10:17 am

    * - Vera should work in a vacuum.

    I like to solve these problems thus:

    * - Jayne Cobb is an idiot and everyone was under too much stress to realize that he is wrong.

    Nope Jayne was smarter than that, he new about “Metal Vacuum Fusion”
    http://www.coolsciencefacts.com/2006/metal.html

    Although the metal will keep the thin layer of oxygen for a while in space, the sliding metal parts that make up a gun would probably weld together very fast once operated.

  71. Carlon 17 Mar 2008 at 10:24 am

    @Ian: the reason we can’t mesh GR and Quantum Field Theory is because we actually live in a Matrix that simulates each of them separately, picking whichever is appropriate to given circumstances but never both at the same time. The creators of our Matrix never anticipated that we would become smart enough to notice how deep-rooted the incompatibility is.

    P.S. There is no dark energy either, it’s just a bug in the cosmological motion simulation.

    ;-)

  72. Earl's TVon 17 Mar 2008 at 10:27 am

    Oh, and since Vera was gunpowder-based, how should she be able to work in a vacuum (i.e., without oxygen)?

  73. The Bad Astronomeron 17 Mar 2008 at 10:39 am

    I updated the Aliens section; I concede. :)

    I shouldn’t have written in my comment above that wormholes violate relativity; I actually do know that the solutions for GR allow such things - it was just a mistake for me to write that!

    But it’s still FTL! It’s not going FTL locally, but it is globally. To an observer on Earth, a traveler can go many light years in a few seconds, and that’s FTL. I can’t comment too specifically on what the actual conduits are in Stargate (I simply don’t remember if they ever say in the movie), though in Contact it’s specifically said it’s an Einstein-Rosen bridge.

  74. Amstradon 17 Mar 2008 at 10:43 am

    Gunpowder has its own oxygen source (potasium nitrate). It should ignite in a vacuum.

  75. Pieter Kokon 17 Mar 2008 at 10:48 am

    Phil, you can’t define a global velocity in a unique manner, because for that you would need synchronized clocks that are lightyears apart. There is just no way to do that in GR.

    You can only define a local velocity, and then you find that at no point do you travel faster than light when you go through the wormhole.

  76. Joshua Zuckeron 17 Mar 2008 at 10:49 am

    Solaris: I think they got it COMPLETELY wrong (as you might see in the io9 comments, where there’s some debate). I’d give it a check mark for FTL I think and not one for any of the three they actually put. Sigh.

  77. Earl's TVon 17 Mar 2008 at 10:56 am

    Amstrad, I didn’t know that about gunpowder. Thanks for taking the time to educate me.

  78. Rob Knopon 17 Mar 2008 at 11:12 am

    Phil, you can’t define a global velocity in a unique manner, because for that you would need synchronized clocks that are lightyears apart. There is just no way to do that in GR.

    This is correct. This is why people like me like to get all hot under the collar and say the the description of the expanding Universe is “galaxies flying apart” and saying that they “move faster the farther away from you they are.”

    On the other hand — we’re using a lot of semantics and pedantics to get around Phil’s basic point that wormholes are FTL. They are, even if we have General Relativity solutions that may allow it. Those who want to argue otherwise should all get over it. Use “closed timelike curves” or some such if you prefer. But getting all bothered that it’s called FTL based on some strict-vocabulary technicality misses the point that what we currently understand about science is skipped for purposes of plot. And, yes, we could debate about which sort of FTL drive is less or more rubber science, but that’s not the level of detail Phil is talking about here.

  79. SkepticTimon 17 Mar 2008 at 11:13 am

    Barton Paul Levenson: your suggestion;

    “See if you can find Miguel Alcubierre’s 1994 paper in Classical and Quantum Gravity for an example of how to do this stuff. Something can move faster than light globally without doing so locally.”

    I assume you mean the following paper:
    arXiv:gr-qc/0009013 v1 5 Sep 2000: “The warp drive: hyper-fast travel within general relativity.” Miguel Alcubierre

    You might also want to consider
    arXiv:gr-qc/9702026 v1 13 Feb 1997 ‘The unphysical nature of “Warp Drive”’

  80. Rob Knopon 17 Mar 2008 at 11:14 am

    This is correct. This is why people like me like to get all hot under the collar and say the the description of the expanding Universe is “galaxies flying apart” and saying that they “move faster the farther away from you they are.”

    Failed to finish my run-on sentence. I meant to say that I don’t like this description, and it’s not a good description. This is the reason that we prefer the “space itself expands” description.

  81. Donnie B.on 17 Mar 2008 at 11:15 am

    Unfortunately, Earl, I think the writers of that Firefly episode had the same misconception that you did. That’s the real explanation of why Vera “wouldn’t fire without air around her”. Anything else is just a fanwank.

    Though the cold welding idea is pretty good. Somehow, though, I can’t imagine it would work that fast, or would form a strong enough bond to overcome the energies imparted by the firing mechanism (which, on today’s automatic weapons at least, is driven by a fraction of the expanding gas from the round).

    By the way, Earl, if bullets needed air to fire they wouldn’t work on Earth either — given that the projectile is sealed tightly into the cartridge.

  82. Pieter Kokon 17 Mar 2008 at 11:23 am

    Hmm, Rob I don’t think it is strictly semantics. Straight FTL as in moving locally faster than c is a different kind of impossibility than travelling through wormholes, in the sense that the former is fundamental and the latter is practical. At least, that seems to be the current state of affairs.

  83. MartinMon 17 Mar 2008 at 11:29 am

    But it’s still FTL! It’s not going FTL locally, but it is globally. To an observer on Earth, a traveler can go many light years in a few seconds, and that’s FTL.

    You’re dangerously close to concluding that everything is FTL. If I drive West from Edinburgh, I’ll reach Glasgow in about 20 minutes. I can, in principle, reach Glasgow by travelling East from Edinburgh, but to get the same arrival time, I’d have to be doing around 12,000 mph. Exactly the same principle applies to wormholes. That a journey between two points would require FTL speeds without a wormhole doesn’t change the fact that travel through a wormhole doesn’t. If an Earth-bound observer concludes that a traveller has managed FTL speeds, that’s only because they’re looking in the wrong direction.

  84. wheatdoggon 17 Mar 2008 at 11:44 am

    RE: moving slowly in zero-g

    Those careful movements in low gravity lead some people to believe that everything moves in slo-mo in space. It came up in class recently when we were talking about projectile motion on the moon. One student said the projectile would move in slo-mo. I said she was partly correct. It would fall slower, but its forward motion would be same as it is on earth. Can’t say she was convinced … Visual depictions are so much more powerful than verbal explanations. Maybe if we could stage a baseball game on the Moon …

  85. TheBlackCaton 17 Mar 2008 at 11:52 am

    As people have said, they do use FTL travel in the Alien series. According to Aliens: Colonial Marine Technical Manual the reason they use cryogenic sleep (”hypersleep” they call it) is because, although to people outside the ship the journey takes days, weeks, or even months, to people inside the ship it seems to take much, much longer. So they go into hypersleep to avoid excessive aging during the journey. Also, according to the technical manual they do literally go faster than the speed of light. I am not familiar with the physics but basically the FTL drive converts all the ship’s mass to tachyons and then converts it back when it arrives at its destination.

  86. xav0971on 17 Mar 2008 at 11:58 am

    Why is everyone talking as if “wormholes” exist. Arguing about something that doesn’t exist is a waste of time. FTL is impossible period. It would require an infinite amount of energy since the mass of the vehicle would increase exponientally as you approach the speed of light Since the universe has a finite amount of energy therefore FTL travel is impossible.

  87. Ian Kemmishon 17 Mar 2008 at 12:22 pm

    2001:

    1) Watch the phase of the earth as seen from the moon during the Ares landing sequence. It keeps flipping from one side to the other in a way which, once you’ve noticed it, is most distracting. (Actually Kubrick repeated this on Earth in Barry Lyndon - “interesting” continuity errors seem to be a signature of his!)

    2) Frank doesn’t conserve angular momentum. He’s spins fast when he’s dying, and slowly when he’s dead.

    3) Someone mentioned twinkling stars. I suspect that this is almost certainly an artefact of the video transfer, and not there on the original negatives. Is there a Blu-ray version? :-)

    Apollo 13:

    I’ve only watched this once, but the big green seven-segment LEDs on the command module computer seemed like an anachronism to me. In 1970 I’m pretty sure you could only have big red LEDs or white incandescent indicators. Unless someone can correct me on this?

  88. asknoton 17 Mar 2008 at 12:31 pm

    Not everyone may agree on this, but I like to think of the term FTL in scifi as applying not to a physics phenomenon, but to a technology.

    Thus, traveling through a natural wormhole is not FTL, but making a wormhole with the intent of using it to get to B from A faster than a photon through normal space is.

  89. Jack Hagertyon 17 Mar 2008 at 1:01 pm

    Rowsdower says: “You might want to check out the Insultingly Stupid Movie Physics page at:
    http://intuitor.com/moviephysics/
    It’s got great stuff that covers more than just sci-fi, but all movie genres.”

    There’s now a book out of his blog entries (much like Phil did with his first book). You’ve got to be careful, though, it really could have used a tech editor. It’s full of little mistakes like using “terminal velocity” when he means “escape velocity” and he refers to the “Challenger” shuttle disaster when he meant “Columbia.” He also oversimplifies some of his equations like cancelling out Pi and the square root of “g” (in metric) because they are sort of close and it made the math simpler.

    A good effort overall, though.

    - Jack

  90. Jack Hagertyon 17 Mar 2008 at 1:05 pm

    Tom K says: “Second (and this isn’t really an error per se), the moon shuttle that takes Dr. Floyd from Clavius Base to the monolith site is shown gliding a constant height over the moon’s surface. This would only be possible if the shuttle were creating a constant downward thrust that exactly matched the vehicle’s weight.”

    Apparently you’ve never seen a model of the moon bus (or looked closely at the external views in the movie).

    The propulsion system consists of six large nozzles pointed straight down. They can gimbal slightly for lateral motion, plus there are pitch/yaw/roll thrusters on the sides.

    I have a book that can help you with this :-)

    - Jack

  91. Jack Hagertyon 17 Mar 2008 at 1:09 pm

    Tom K says: “The third error (and really the only Major one in the film) occurs when Dave is in the pod, moving out away from Discovery to retrieve Frank’s body. A number of shots are shown from Dave’s point of view looking out the front window, showing the stars moving horizontally across the field of view. In fact, the stars should be stationary as the pod is moving in a straight line - the stars would be perceived as moving across the field of view only if the pod were rotating about its vertical axis.”

    Absolutely correct, but it was done for the reasons you mention (to impart a sense of motion to the audience). You may not have noticed that he does this for Discovery, too, when the outside is viewed through the open Pod Bay doors.

    “I haven’t seen this flaw mentioned anywhere else whenever 2001 is discussed (although I haven’t exactly researched it thoroughly).”

    Like I said, I have a book that can help you with this :-)

    - Jack

  92. amonra1979on 17 Mar 2008 at 1:17 pm

    2001:

    If you’ve read any of the Space Odyssey books, I think the later books explain that what actually happened to Bowman is that he was incorporated into the monolith. He is seeing the vast knowledge that it has accumulated. Dave is pretty much present in all of the Space Odyssey books in some form or another. I can’t quite remember reading 2001, but I think even in there it explains it as the monolith communicating with him. That was my interpretation of the movie as well.

    Of course what I read in the later books could just be a correction on what Clarke saw as a blemish. If I remember right, he wrote the later books as if the original 2001 took place around Jupiter, when it actually took place around Saturn. Probably to interest those people who saw the movie, then went to read his books.

  93. Jack Hagertyon 17 Mar 2008 at 1:17 pm

    Brown says: “Scott Carpenter, who was treated as something of a goat after his mission … is treated by the book in a surprisingly heroic fashion. Carpenter had a lot to do in space, and he tried to do as much as he could. Carpenter was enthused by how much he’d been able to accomplish in space, but his accomplishments were largely forgotten. Rumors circulated that Carpenter had lost his head during the flight. The rumors were false, but the damage to Carpenter’s reputation was done. He never flew in space again.”

    You ought to read Chris Kraft’s account in his autobiography “Flight, My Years In Mission Control.” Carpenter comes off as a complete incompetent who was basically fired (by Kraft) after screwing up his flight. Of course, they had to come up with the cover story of Carpenter wanting to do deep sea research since all of the astronauts were “heroes” and couldn’t be publicly faulted. I suspect the truth is in between. In Gene Kranz’s book (”Failure is Not An Option”), which I read back-to-back with Kraft’s, he comes off closer to the way you described.

    - Jack

  94. Jack Hagertyon 17 Mar 2008 at 1:20 pm

    Brown says: “Another 2001 flaw: Watch the space station. It rotates in one direction (say, clockwise), then suddenly is seen rotating in the other direction (counter-clockwise). Check it out!”

    I’ll have to do that. Kubrick did cut the POV back-and-forth from the front of the station to the back when showing the Orion docking. That would have the same effect.

    - Jack

  95. JackCon 17 Mar 2008 at 1:25 pm

    I used to play with 7-segment LEDS in the mid-70s - they had been around for a long time. Prior to being discreete elements you could buy at your local ICs Unlimited in the late 70’s for a few dollars, they were much more expensive seperate lamp versions - and even electron tube versions - sort of.

    Keep in mind that everything in the ship was years old to start with. It is virtually impossible to get anything “up to date” in the modules because of the time it takes to check how it operates with everything -and I do mean everything - else. Years. I think I was once told it takes over 6 months just to change a single programming parameter on the Shuttle. Or - it did, long ago.

    Apollo was worse - much worse - for getting new gear aboard. I am sure that even the astronauts were amused by the quaint, old gear they had to use.

    This Wiki article indicates (kind of) that an incandescent version may have been available in the 50s - which seems about right: http://en.wikipedia.org/wiki/Seven-segment_display

    Regarding “errors” in 2001 - my absolute favourite movie of all time, we have to remember when it was made (1968) and that it was NOT written by Clarke (he did the book from the screenplay). I believe I recall there were at least 4 “definate errors” identified in the film later by Clarke, and a few others that sneak in, but there were also some items put in “purely for art’s sake”.

    With all that Kubrick got RIGHT, I am more than happy to give him a pass on a (very) few misses.

    JC

  96. Ken_g6on 17 Mar 2008 at 2:00 pm

    Lessee…

    In 2001, they do not have FTL travel. Dave my think he’s flying through the galaxy, but as we get hints about in 2010 and learn for sure in the book 3001, he was absorbed as a program in the giant machine that is the monolith. Also, in that book, FTL travel is impossible even for whatever race built the monoliths; otherwise, Earth would have been destroyed in 2100 or something.

    For Armageddon, as you mention in your review, there were small asteroids floating around the large one. That’s what they mean by “Asteroids or other objects shouldn’t be able to float close together without falling into each other’s gravity.”

    Finally, I know you’ll never watch Mission to Mars again, but the alien spaceship at the end wasn’t designed for FTL; just for high acceleration. That’s why they used the breathing fluid.

  97. Brownon 17 Mar 2008 at 2:01 pm

    Jack Hagerty says: I’ll have to do that. Kubrick did cut the POV back-and-forth from the front of the station to the back when showing the Orion docking. That would have the same effect.

    My recommendation: when you see the station for the very first time, pick a side, either the finished side or the side under construction, and determine which way that side is rotating (clockwise or counter-clockwise).

    There will come a scene a few seconds later in which Earth appears, and the station comes looming in from the side of the screen, and the Orion is approaching the station. The station is now seen from a different angle, but you can check to see whether the side you picked earlier is rotating in the same direction was as it was previously.

    It is, of course, not impossible for the station to come to a stop and change direction; but this would be very difficult to do (and totally impractical) within a few minutes, as the film implies.

  98. Koremanon 17 Mar 2008 at 2:13 pm

    Not physics in general, lightning always seems to strike within 10 meters. When actors are calling the person on the other side of the line is speed talking most of the time. Quite some cars have serious problems with their tires when accelerating or breaking. In case of an emergency stop the road in the scene may shows lots of skid marks, even if it is in the middle of the desert. The only actor using the bathroom seems to be Al Bundy. Most cars explode with tremendous shock waves after an accident. Sometimes twice. People on speeding vehicles are not bothered by air pressure. People in action movies always find time to have their hair done. Bullets whistle. Computers make geeky sounds. Laser guns always fire beams of light that travel slow enough to see them move. Robots are never connected to the internet. E-mail cannot be traced by looking at the headers.

  99. Mark Martinon 17 Mar 2008 at 2:15 pm

    As it turns out, there are many interesting subtle errors in 2001: http://www.imdb.com/title/tt0448134/board/thread/94322938?d=98132968&p=1#98132968

  100. sublunaryon 17 Mar 2008 at 2:37 pm

    As a huge dork and Whedon fan I feel the need to comment on the Firefly ep with Vera firing in space. I read an interview with Joss Whedon (where and when I forget, but I know it was real.) Where he said the reason they did that was that he had no idea if a gun could fire without oxygen and that he had a 50% chance of being wrong.

    So he could do what he did and if he was wrong blame it on Jayne not knowing physics.

    Or he could film it firing in a vacuum and if he was wrong, be yelled at by his science-savvy fans, and feel kind of dumb.

    I personally think it’s sad that he couldn’t find anyone who actually knew the answer. Apparently there are plenty of people out there who do.

  101. Cuspon 17 Mar 2008 at 2:49 pm

    Sigh -

    local FTL is not possible, but global is.

  102. Adelaon 17 Mar 2008 at 4:38 pm

    Stargate has ships that travel FTL with hyper drives. Even in the movie Ra has his big ass gold plated pyramid ship coming in for a landing which they ring beam a nuke onto.
    Alien 4 has a trow away line when the ship on approach to earth shifts engines and the characters hear it feel it and mention that they have dropped out of hyper space, FTL.

  103. Mark Martinon 17 Mar 2008 at 4:46 pm

    Well- even global FTL isn’t really kosher in GR. What GR does allow is the rate at which two pieces of real estate change their distance to compound as the distance itself changes. Two small regions can be traveling apart or toward one another at greater than c, but they cannot do anything useful with this relationship.

  104. defectiveroboton 17 Mar 2008 at 5:06 pm

    RE: Stargate

    Not to wade too deeply into the wormhole-is-FTL debate, but there was one moment in that movie that bugged the poop out of me (well OK, no, not just one moment, the whole movie sucked, but work with me here): When they enter the stargate with the tracking device, it tracks them across the galaxy in real time.

  105. Cuspon 17 Mar 2008 at 5:25 pm

    > Well- even global FTL isn’t really kosher in GR. What GR does allow is the rate at which two pieces of real estate change their distance to compound as the distance itself changes. Two small regions can be traveling apart or toward one another at greater than c, but they cannot do anything useful with this relationship.

    This is incorrect - the Alcubierre warp drive does globally transfer a piece of space at global speeds exceeding c, but locally the velocities are all subluminal - With it, you can get from here to there faster than light would on its own.

  106. ARon 17 Mar 2008 at 5:56 pm

    Pieter Kok: Straight FTL as in moving locally faster than c is a different kind of impossibility than travelling through wormholes, in the sense that the former is fundamental and the latter is practical. At least, that seems to be the current state of affairs.

    Faster than c with respect to what? There is no such thing as local velocity.

    MartinM: You’re dangerously close to concluding that everything is FTL. If I drive West from Edinburgh, I’ll reach Glasgow in about 20 minutes. I can, in principle, reach Glasgow by travelling East from Edinburgh, but to get the same arrival time, I’d have to be doing around 12,000 mph. Exactly the same principle applies to wormholes. That a journey between two points would require FTL speeds without a wormhole doesn’t change the fact that travel through a wormhole doesn’t. If an Earth-bound observer concludes that a traveller has managed FTL speeds, that’s only because they’re looking in the wrong direction.

    You’re completely ignoring one of the basic axioms of general relativity, which is that all frames of reference are equally valid. If there exists any frame of reference which could observe FTL travel to have occurred, then you’ve lost either relativity or causality.

  107. Tom Markingon 17 Mar 2008 at 5:58 pm

    “The only movie on their list I’ve never seen is Solaris, so there might be something there too”

    I believe the web site is referring to the original 1972 Russian version and not the 2002 remake starring George Clooney. I haven’t seen the remake but I have a copy of the original:

    http://www.imdb.com/title/tt0069293

    The original movie was directed by Russian director Andrei Tarkovsky and it’s totally awesome. If you ever get a chance to see it I would highly recommend it, although you’ll have to get the version with English subtitles. I’m not sure I would even classify it as a science fiction movie but rather a psychological thriller.

    Tarkovsky is one of the few cinematic geniuses of the 20th century. I would put him on a par with Stanley Kubrick. Another one of his classics you should check out is “My Name is Ivan” made in 1962:

    http://www.imdb.com/title/tt0056111/

    It tells the story of a 12-year old Russian boy fighting the Nazis in World War II. Very good movie if you can find it.

  108. Mark Martinon 17 Mar 2008 at 6:02 pm

    Cusp,

    I’m not sure I agree with that interpretation of the Alcubierre process. My understanding is that the negative energy condition generates translational motion by expanding space to the rear and compressing it to the front. The transformation would be locally consistent with SR and would compound, just as with the background expansion of space. It would not however amount to a global transaction over arbitrarily large distances at greater than c.

  109. Tom Markingon 17 Mar 2008 at 6:05 pm

    “You’re completely ignoring one of the basic axioms of general relativity, which is that all frames of reference are equally valid. If there exists any frame of reference which could observe FTL travel to have occurred, then you’ve lost either relativity or causality.”

    You first have to define the terms of the debate. For example, if I enter a rocket ship with a constant thrust of 9.8 newtons per kilogram and point it at the galactic center 26,000 light-years away, and then halfway through the journey turn the ship around and decelerate with the same thrust per kilogram, then I can arrive at the galactic center in only 20 years ship-time. Is that FTL travel? I travelled 26,000 light-years in only 20 years or effectively at a speed of 1300c. There is no wormhole needed at all in this case.

  110. Cuspon 17 Mar 2008 at 6:10 pm

    > I’m not sure I agree with that interpretation of the Alcubierre process. My understanding is that the negative energy condition generates translational motion by expanding space to the rear and compressing it to the front. The transformation would be locally consistent with SR and would compound, just as with the background expansion of space. It would not however amount to a global transaction over arbitrarily large distances at greater than c.

    The Alcubierre bubble can move at >c - there is a great illustration of this in Hartle’s textbook Gravity - but at all points, the local velocities are <c (i.e. motions are all within local light cones).

  111. ARon 17 Mar 2008 at 6:12 pm

    Tom Marking: For example, if I enter a rocket ship with a constant thrust of 9.8 newtons per kilogram and point it at the galactic center 26,000 light-years away, and then halfway through the journey turn the ship around and decelerate with the same thrust per kilogram, then I can arrive at the galactic center in only 20 years ship-time. Is that FTL travel? I travelled 26,000 light-years in only 20 years or effectively at a speed of 1300c. There is no wormhole needed at all in this case.

    Are you seriously asking that? If you know enough about relativity to calculate time dilations you should be able to answer that yourself.

  112. Cuspon 17 Mar 2008 at 6:12 pm

    ps - Natario (sp?) showed that the expansion and contraction in the warp drive is not needed to get the same >c travel.

    I love the Alcubierre warp drive :)

  113. Mark Martinon 17 Mar 2008 at 6:17 pm

    Cusp,

    I understand that, and it’s what I’ve been saying. But I don’t think it amounts to global FTL. I think it amounts to a clever adaptation of what Nature is doing with the Big Bang, and that isn’t global FTL.

  114. ARon 17 Mar 2008 at 6:21 pm

    I should probably answer Tom Marking’s stupid question for the benefit of those who don’t know relativity. It is true that it is possible to travel to the galactic core in 20 years, but the rocket crew would observe the distance to the galactic core to be much less than the 26,000 light-years that those on Earth observe it to be due to length contraction. Hence, from their perspective, they travel a much shorter distance in 20 years, and from Earth’s, they travel a very large distance over an appropriately large amount of time. Hence, no FTL occurs in any frame of reference.