Bad Movie Physics: The Science Behind the Disasters

[rohanprabhu]

http://io9.com/assets/resources/2008/03/badmovsci2.gif

 

[Argentum Vulpes]

I'd have to disagree with the two of the problems marked out for Serenity, in the opening five minutes of the movie they explain why the habitable planets have Earth similar gravity and climate, they terraformed said planets to be like earth. This is sci-fi that is being discussed, I'm willing to let that explanation fit for climate and gravity.

I can't believe that they didn't have Star trek on there but then again it would have a check in every category.

 

[jostpuur]

I thought the Space Odyssey vacuum case was fine It was a short exposure to vacuum only! Should the man have blacked out in an instant, or what's the reality if the movie was wrong?

 

[_Mayday_]

I thought some guys tried to prove that everything in start wars was possible or something along those lines, I thought he/she wrote a book on it...?

 

[jostpuur]

I thought some guys tried to prove that everything in start wars was possible or something along those lines, I thought he/she wrote a book on it...?

He/she better try pretty hard!

Most of the stuff is very technology oriented. You can always speculate, that perhaps new discoveries in theoretical physics enable new kind of technology. However, the latest star wars (edit: hmhmh... or was it the second latest? I'm not sure. I'm not a star wars freak. Episode 2 or 3 anyway...), for example, contains quite Newtonian physics defying stuff! In the beginning there is the fight scene in space:

A droid hangs on the wing of a fighter. When the droid gets broken, it falls of, apparently trying to get to rest while the fighter continues with constant velocity?

The big spacecraft gets broken and starts falling towards the planet. It starts leaning while in free fall, and the people inside slide downwards, apparently because of the gravity? (Perhaps it was so big craft, that the tidal effects were notable? )

 

[DaveC426913]

A droid hangs on the wing of a fighter. When the droid gets broken, it falls of, apparently trying to get to rest while the fighter continues with constant velocity?

The big spacecraft gets broken and starts falling towards the planet. It starts leaning while in free fall, and the people inside slide downwards, apparently because of the gravity? (Perhaps it was so big craft, that the tidal effects were notable? )

Yeah, what was that all about George? Maybe having grandchildren makes your brain turn to fluff?

 

[_Mayday_]

Give this a read. It's trying to explain the sound in space idea.

http://en.wikipedia.org/wiki/Physics_and_Star_Wars#Sound"

 

[rohanprabhu]

Give this a read. It's trying to explain the sound in space idea.

http://en.wikipedia.org/wiki/Physics_and_Star_Wars#Sound"

wikipedia says:

First, it is possible that the various ships’ deflector shields, when hit with radiation from explosions or blasters, cause the ships themselves to vibrate, producing sound.

even if a ship did vibrate.. u would need to be directly in contact with it to 'feel' sound.. not that u could still hear it. Like.. just by touching a speaker cone, you can just 'feel' sound.. but not hear it.

by 'direct' contact i mean the presence of medium between the two among which a pressure wave can be carried...

 

[DaveC426913]

even if a ship did vibrate.. u would need to be directly in contact with it to 'feel' sound..

Hang on a sec. How is this a special case? If the ship is vibrating, then you are in contact with it just like you are in any other ship that's vibrating, say, due to engine noise.

 

[Poop-Loops]

FTL travel is bad science because science hasn't figured out how to do it yet. Great.

The laser bit always annoyed me, but I always tell myself it's something other than lasers.

I don't know what it means by "nearby asteroids aren't pulled in by gravity". If it's a planet, it could be in a stable orbit around it. If it's a space station, it wouldn't have enough of an impact to see any immediate results, would it?

Easy communication with aliens? What does that mean? If you assume the Star Wars universe, then it's because they've mingled for centuries... of course communication would be easy. If it means FTL communication, again, go back to point 1 about FTL travel.

All planets have Earth gravity: This bit annoyed me on alien-inhabited planets, that they all breathe oxygen and have the same gravity. But for human planets, why would we go for planets that aren't similar to Earth?

The part with mono-climatic planets always annoyed me, too. It's just plain stupid. I figure they did it to differentiate between the planets. If all planets had Earth-like climates, i.e. they were widely varied, the planets wouldn't have that sort of "magic" they do currently, i.e. Hoth is all ice, etc.

 

[Cyrus]

Hang on a sec. How is this a special case? If the ship is vibrating, then you are in contact with it just like you are in any other ship that's vibrating, say, due to engine noise.

Well because of the inertial dampers, obviously. Laforge, out.






...damn, I am a nerd.

 

[DaveC426913]

FTL travel is bad science because science hasn't figured out how to do it yet. Great.

No. FTL travel is bad science because science tells us it can't be done. It violates physics.

It's no different from sound transmission in space. Sure, we could fantasize that some day we will be able to transmit sound through the vacuum of space - but the simple fact is: it violates physics as we know it.

 

[f95toli]

The problem is of course that if the movies were realistic the storytelling would suffer. It is no secret that e.g. the space combat in Star Wars was inspired by the dogfights during WWI.
I recently read a short story where the combat was probably somewhat more realistic.
First of all, everything was obviously handled by computers (considering human combat pilot will probably be gone in just a few decades this is probably a very good guess).

Secondly, the ships were moving very fast (a few % of c) as you would expect for ships that can fly between planets in a reasonable amount of time, and were never closer than a few thousand km from each other. Hence, to Immelmanns.

Thirdly, there were no mysterious "shields" meaning the fights were over after a few of microseconds; one hit from a "sweeping" laser or a relativistic Gauss gun (a small pebble accelerated to a few % of c, is probably enough to destroy most structures including space ships.

It was a pretty good story (unfortunately, I can't remember the name) but I don't think it would work on the big screen; combat sequences that are only a few us long would be pretty boring to watch.

 

[f95toli]

No. FTL travel is bad science because science tells us it can't be done. It violates physics.

I don't quite agree. Travelling FTL does not nesscarily violate SR as long as you are not trying to reach speeds >c.
I am of course talking about "wormholes" etc. They are unlikely to exist, but the point is that they do no violate physics as we know it and we can't rule them out completely. This is still very much an active field of research and as far as I understand this is something that many cosmologists take very seriously, IF stable wormholes do turn out to exist it will have important consequences (whether or not we could use them to travel is perhaps less important).

"It violates physics" is a rather strong statement, we need to be careful about how we use it.

 

[Poop-Loops]

Exactly. Nobody ever says "We are putting rockets on our ship and we will go as fast as the speed of light using this method."

It's always something like "Hyperspace" or what have you, that implies going through some "alternate dimension" or worm holes, etc. That's how it was in Event Horizon, at least.

 

[DaveC426913]

I don't quite agree. Travelling FTL does not nesscarily violate SR as long as you are not trying to reach speeds >c.

FTL means, literally, faster than light. This violates the laws of physics as we know them.

Wormholes and other of zip-from-here-to-there devices are not (at least in my books) bad science, as there's no laws of physics (that we know of) violated. Making-the-distance-travelled-shorter-so-you-get-there-in-less-time-than-light-would does not, I would argue, count as faster than light.

The chart does seem a bit arbitrary on this. Star Wars has drives that get you from here to there zippity-quick, but they don't think the same thing applies in Contact?

 

[_Mayday_]

UPDATE

http://img151.imageshack.us/img151/8063/pfmoviejm2.png ​

[/URL]

 

[Jimmy Snyder]

A laser is a faster-than-light weapon?

 

[_Mayday_]

A laser is a faster-than-light weapon?

1. The weapons are faster than light which can't be so.
2. If they were to be faster than light, you would not be able to dodge them.

 

[Jimmy Snyder]

1. The weapons are faster than light which can't be so.
2. If they were to be faster than light, you would not be able to dodge them.

And a laser is an example of such a weapon? I saw Moonraker, and I don't remember any faster-than-light weapons.

 

[_Mayday_]

And a laser is an example of such a weapon? I saw Moonraker, and I don't remember any faster-than-light weapons.

I haven't seen it, but neither did I make the poster, the original is in the first post. It may be that 'fatser than light' was mentioned once.

 

[Jimmy Snyder]

The Socratic method has met its match. A laser is NOT a faster-than-light weapon.

I have not seen Wallace and Gromit, but I believe it is a claymation film. A dog that talks violates several principles, perhaps some of them physical, but a blob of clay molded into a stylized image of a dog that talks is beyond the pale. If the crudicasean theory of lunar material appears in that film, it is probably the closest approach to reality made in the whole film. None the less it's been debunked. Even so, I doubt that it violates any physical laws .