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Can energy be condensed and/or bridged?

  1. Jun 27, 2010 #1
    This is something that has come to mind and I would want to hear what you other enthusiasts also think about it if you find it at all intruiging. The concept I am thinking about can be applied to a variety of processes but once the extent at which the idea surpasses customary principles it becomes quite enigmatic. What happens to an item that gains potential energy and is forced to keep increasing inherent power with an infinite capacity, but is also kept from transferring into kinesis. How would a capacitor react? Can energy be condensed and/or bridged?
  2. jcsd
  3. Jun 27, 2010 #2
    Re: Capacitors

    Well, a capacitor can only hold so much charge depending on design. Then it either stops being able to be charged, or it is destroyed.
    Infinite capacity, in this context, is not possible.
  4. Jun 28, 2010 #3
    Re: Capacitors

    If you continue to pour energy into a real-world system, you reach a point where
    a) the system runs out of capacity or b) you run out of energy.

    If you postulate the availability of infinite capacity and infinite energy you would need an infinite universe both to supply it and to contain it.

    Thinking about it, probably one wouldn't be enough...
  5. Jun 29, 2010 #4
    Re: Capacitors

    Well ofcourse for a finite system but how much energy can be infinite in power
  6. Jun 29, 2010 #5
    Re: Capacitors

    Well, power is the rate-of-doing-work, which is the same as the-rate-of-storing-energy.

    So for infinite power, you would have to store infinite energy, infinitely fast...

    That sounds remarkably like the moment of creation of an infinite universe. or possibly the destruction of one. :biggrin:
  7. Jul 2, 2010 #6
    Re: Capacitors

    I guess what is 'potential' energy versus what is 'kinetic' energy is relative. If you pour an infinite amount of energy into accelerating an object, it will keep absorbing that energy (faster speed/bigger mass). Relative to you the object transfers that energy into kinetic energy but relative to itself, it is not moving and it is all potential energy.

    Of course Einstein then would have to say that the mass increases to an infinite size and consumes the entire universe.
  8. Jul 2, 2010 #7
    Re: Capacitors

    This is a silly topic and I shouldn't have contributed, but I can't let that pass, it's fallacious.
    Not only that, it perpetuates the OP's initial misunderstanding.

    Energy isn't some thing like a liquid that you can pour from one place to another, it's a book-keeping device that we use to keep track of the movement of, and forces between objects.

    Nor does an object exist in relation to something called the 'universe', it exists in relation to other objects. Energy is a measure of that relationship so that you cannot talk about the energy of an object, only it's energy in relation to another.

    In a 'universe' that consisted of just two objects, moving relative to each other, one would have an energy (classically) of 1/2mv^2 relative to the other. The other would have an energy of 1/2mv^2 relative to the first.
    (K.E. is vectorial so the two energies would be directed in opposite directions, making the vector sum zero.)
    The energy of either object, relative to a third would be a function of it's relative velocity. Every time you move the frame of reference, you change the zero point for measurement of energy.

    Since an object doesn't move relative to itself, it's KE relative to itself is zero. Potential energy doesn't come into it.
  9. Jul 2, 2010 #8
    Re: Capacitors

    I kind of like this topic actually, it's a nice philosophical "What if" question. It's good to think this way to give additional points of view. For instance, if we say that body A accelerates away from body B, then A acquires a Kinetic energy relative to B. But as you say, relative to A, it is not moving and has no kinetic energy - but from its point of view, B has the kinetic energy since it appears to be the one accelerating away. In other words, to each, the 'other' has the kinetic energy. In this respect, and according to a 'relativistic' point of view, you are completely right. Neither has any 'potential' energy.

    However...stepping outside the 'norm' for a moment and contemplating and interesting point of view (not according to the books necessarily), in the scenario above, only A would have experienced the force of acceleration. This force of acceleration is non-inertial movement. This non-inertial movement then means that the Principle of Relativity cannot apply to the situation and the experience of the object in one frame of reference cannot be translated into the experience of the other, since this Principle fails when trying to explain non-inertial movement. Similar to what we see with the Twin Paradox, object A in this case "COULD" be considered the one to have received all the energy that was transferred from some other form, and not B, because only A felt the non-inertial movement. So from a philosophical point of view, one could scratch their head and think that A must have increased in energy somehow and not B, hence acquiring what might be described as a type of potential - or even 'rest' energy.

    Keep in mind that the twin paradox is only a paradox when the non-inertial movement is ignored. Most people agree that the paradox goes away when taking the acceleration into account but then the debate between absolute vs relative space ensues. The "Absolute relativism" versus "Absolute space" debate is still not resolved, however, many think it is solved simply because they sit on one side and are convinced of their own point of view. Regardless, the debate continues with strong arguments on both sides, so it is not certainly wrong to consider that the situation is not perfectly relative.

    In the end, your argument depends on the fact that the points of view between A and B are perfectly relative - which would require that no non-inertial movement was involved, but this is not the case.
  10. Jul 2, 2010 #9
    Re: Capacitors

  11. Jul 2, 2010 #10
    Re: Capacitors

    Ha, talk about a come-back argument that is 'out of the box.' Yeah, it's a good point. But I guess the nature of the original comment on this particular thread wasn't really a high school type of question and was more of a thought-inducing philosophical question.
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