2

Something I was wondering about: according to Newton’s 3rd law every action has its reaction. So, if I push something, I have to cope with the same force I am pushing it with acting on me, too.

But that should also apply when I am using the Force (I am pushing someone remotely), i.e. when I use the Force to throw or push something, the thing exerts a reaction.

Where does this force go? Onto the user? That would be impossible, especially when Yoda lifts the X-Wing out of the swamp (weight of the X-Wing >> assumed real (not Force-enhanced) strength of Yoda)?

Or are the Jedi using a supporting place where they can target the reaction of the moved object, i.e. guiding the reaction force to this place? In this case the Jedi would have to look first what their supporting place is, because if they are using something unstable it could happen that it collapses. Or (best explanation) did I simply miss something?

11
  • 9
    My guess: it goes onto the midichlorians. Mar 5, 2015 at 12:56
  • 17
    “That would be impossible” — of course, the Force is impossible in the first place. Mar 5, 2015 at 12:58
  • 4
    The answer is probably quantum.
    – Deltharis
    Mar 5, 2015 at 13:29
  • 3
    Since the effort they are expending is mental, the return force is mental. They generate a force construct with their minds, and use it to push an object. All opposite reactions happen to that construct, which is composed of mind energy and absorbs it, which is fatiguing on the Jedi as they turn that opposite force into entropy. There, enough technobabble for you? If not, I can tackle lightsabers and using parsecs to measure time.
    – Jeff
    Mar 5, 2015 at 14:20
  • 6
    For a canon that has sound in space and measures time in parsecs, I think you're on a loser trying to apply (or explain anything in terms of) realistic physics, to be honest.
    – user8719
    Mar 5, 2015 at 18:30

4 Answers 4

14

There's a nice wikipedia article on how the Star Wars physics is wrong not just for the fictional lightsabers and hypothetical planets, but even the physics of sub-lightspeed spacecraft. Specifically, the Millennum Falcon always make banked turns, even though this is just something planes do because they fly in an atmosphere.

When the physics isn't correct even in scenes that should have conformed to known physics, it's no surprise that the Star Wars magic is out of alignment with Newton too.

In fact, why not add violation of Newtons third law in the x-wing lifting scene to the wikipedia article?

4
  • 11
    Simple - Yoda didn't life the X-Wing. He just held it still and pushed down the planet.
    – Jeff
    Mar 5, 2015 at 14:09
  • 19
    I make banked turns when I play Descent, even though I have no restriction to do so. Reasons include it's simpler on the controls, but also it feels less disorienting. While banking may not be required in space, personally I find it more comfortable - at least in a game :p Mar 5, 2015 at 15:39
  • @Jeff Violates the third law even worse. The planet should have pushed back with equal force, which would most likely send Yoda flying into space or at least high into the atmosphere (due to Yoda's immensely smaller mass).
    – jpmc26
    Mar 5, 2015 at 17:39
  • 6
    @jpmc26: That's the joke. Pretty much any time someone uses the Force, they're essentially saing, "Physics, we don't need you here. Go sit in the corner and cry because I'm doing SCIENCE!" 'Science' in this case is the same sort that lets Iron Man stop without becoming red paste and Mr. Fantastic stretch.
    – Jeff
    Mar 5, 2015 at 19:25
5

In regards to Yoda lifting the X-Wing, why would the return force have to be directed back at the Force user? If I can project a pushing force forward into an object, why couldn't I project the return force down into the ground in order to brace myself. This isn't to different from putting a foot back to brace myself while shoving something heavy. It's just a mental foot instead of a physical one.

7
  • 1
    As already mentioned, in this case the jedi would always have to take care where he puts his mental foot, otherwise he would have the problem that if the surface collapses his mental foot looses stability, and everything else, too...
    – arc_lupus
    Mar 5, 2015 at 20:22
  • 1
    @arc_lupus Yes! Which could lead to some great dramatic moments! But for an in-universe answer, you could just spread that force out over a really large area. Also since the pushing force isn't physical, the return force wouldn't have to be physical. Meaning if you are moving things by manipulating the fabric of the universe, then the mental foot could be braced against the fabric of the universe, and not something so mundane as dirt. If this is the case, then the biggest question is why Jedi don't fly everywhere by manipulating the fabric of the universe...
    – AndyD273
    Mar 6, 2015 at 14:37
  • The pushing force has to be physical to have an influence onto the pushed (physical) particle.
    – arc_lupus
    Mar 6, 2015 at 14:43
  • @arc_lupus Right, like gravity... :) If you look at gravity as a dip in space time grahameb.com/realitycheck/wp-content/uploads/2013/08/… it's not a physical force, but it definately has an effect on physical particles. Of course it's all silly, but it could be done without breaking the laws of physics. And if you think about it, a lot of quantum physics seems to go against Newtons physics and no one knows why, yet.
    – AndyD273
    Mar 6, 2015 at 15:09
  • Well, as far as I know the Higgs-particles are physical...
    – arc_lupus
    Mar 6, 2015 at 15:13
2

One possibility is that the force pushes equally against the fabric of space-time. The 'equal opposite reaction' is spread out throughout all the midichlorians in the universe.

Another option is that the reaction force is shunted into hyperspace by some unknown method.

2
  • So - because magic? (with science-y buzzwords applied)
    – RDFozz
    Oct 25, 2018 at 21:49
  • @RDFozz Technobabble is and always will be my favorite form of magic.
    – Shane
    Oct 27, 2018 at 4:16
1

We aren't told what is mechanically happening when someone "uses The Force" to push something. Since, as you observed, this seems to have zero effect on the body of the Force-user, I think it works differently in some unspecified way. I like your idea that the Force-user needs to also apply an opposite force to something else nearby, but I know of no scene which says so.

According to Obi-Wan Kenobi:

The force is what gives a Jedi his strength. It's an energy field created by all living things. It surrounds us and penetrates us, it binds the universe together.

It seems likely that the opposite force goes against this energy field, rather than against other physical object.

What bothers me more, is the scene in Episode II where both Obi-Wan and Anakin non-chalantly leap out of windows and air cars and collide with things at high speed without being hurt. I would expect Obi-Wan to have broken his hand catching Anakin's light saber, and Anakin to have broken many bones falling a great distance onto the top of the assassin's air car, etc.

Not to mention practically everything about the "pod race" scene in Episode I...

1
  • 1
    This is very similar to my own interpretation of how 'the Force' "works". A force user is not taking action themselves, they are directing something much more powerful than themselves to do it for them. A crane operator isn't smashed in to the ground due to equal and opposite reactions just because he 'uses' the crane to lift something that is otherwise heavy enough to do so. In this sense, the force is a tool, like the crane, doing the lifting/pushing/pulling. Since the force binds the universe together, the equal and opposite reaction is applied to the whole universe by the force itself.
    – Harthag
    Oct 25, 2018 at 14:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.