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Gravity Weapon

  1. Jul 10, 2013 #1
    I recently watched Superman-Man of Steel. In the movie used some sort of gravity weapon to divert missiles. It also showed one thing they called 'The World Engine' to modify earths gravity.

    When considering Gravity just another field like Electric field(to which it is very similar to). We do easily can change Electric field of place easily.

    So, is that sort of gravoty weapon(modifier) possible in future or in present(might already be in use and not in my knowledge), Or is it just a fiction and remain fiction?
  2. jcsd
  3. Jul 10, 2013 #2
    It is a universal law that every aspect of science can and will be used to create some sort of weapon. When it comes to gravity I recon that it won't be used for more than directing missiles and cannon balls.

    But to actually get to your question, I think there are two important facts that make electric forces quite different. Even ignoring electrodynamics, the proportionality constant between the electric force and charge is not the (inertial) mass. That is, a charged object resists acceleration due to a parameter that is completely separate from the electric charge. This is not true for gravity. Also, the existence of a negative charge makes control of charged objects quite different.

    On top of that, apart from tasers, I don't think there are any "electric" weapons. It would be very difficult to change the Earth's charge in any meaningful way.

    My estimate is that there will not be any gravity weapons in the next few centuries. But fear not! As soon as the technology is available, I'm sure we will build black hole missiles that can force any object in the universe to collapse into a black hole.
  4. Jul 11, 2013 #3


    Staff: Mentor

    There are a couple of difficulties with controling the gravitational field compared to controling the electric field. The first is that you can use negative electrical charges to cancel the field from positive electric charges, but there are no negative gravitational charges. The other is the strength of the interaction, the gravitational force between two protons is many orders of magnitude smaller than the electrical force between them.
  5. Jul 14, 2013 #4
    Good answers!

    I know that the magnitude of gravitational force is much smaller as compared to Electrical Forces, but this is the present situation or say the situation at Earth where we have masses of very less density. I am talking about black holes here, but is it would be possible to design some sort of high density masses with some technology, which can effect the Gravitational Field of Earth, in the similar fashion magnetic field of earth can be modified easily.

    Has someone ever tried to do so, i mean some failed attempts or something?

    One more thing which might be off-topic: What about negative masses? Do they have existence in any theory?
  6. Jul 15, 2013 #5


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    Staff: Mentor

    A thousand misinformed crackpots perhaps. It just doesn't work that way.

    Not in any accepted mainstream theory, no.
  7. Jul 15, 2013 #6


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    Staff: Mentor

    Thread closed for a bit.
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