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Quantum Leaping & Perpetual Motion?

  1. Aug 14, 2009 #1
    Hi all Ill start with saying I am very new to all this. I am a very geometric oriented person and I view things as images and not equations. So most times I can figure out and know how things work but I just can't explain how they work in terms or equations. I have just started studying quantum physics and could possibly use some adjustments to my perception in the matter so I could be misunderstanding but here goes... I am wondering if I could get the opinions and teachings of some people here who are allot smarter than I :redface: about this thought that popped into my mind. Again... maybe this is already out there as part of a theorem but as I stated I am new and haven't study in depth yet about quantum physics.

    So on the thought of perpetual motion. We have seen and heard much about this "coined" phrase of perpetual motion. Most people don't understand its implications and thus use the term incorrectly when speaking about a well engineered system that "appears" perpetual at the finite moment but in actuality is a digression of energy rather then a constant with no loss.

    It came to mind today. I remember reading how in quantum physics electrons seem to "quantum leap" thus it is impossible to locate their exact location at any given moment. Quantum leaping suggesting electrons are existent inter dimensionally. Leaving one dimension to another and back again giving the illusion that they are "disappearing" and "reappearing" in and out of existence. My thought was this. Is their proof that the system of the atom is one that digresses with time according to the "laws" of physics or is it actually a system which maintains and equal energy through time. If it digresses I may be off track. Do we die because our atoms slow down and destabilize or do we die because we in our dimension fail because our laws of physics state we have expended our maximum out put as a being.

    OK so the core of my thought... if electrons quantum leap wouldn't that mean they essentially enter a different dimension and for that time while existing in that dimension they share the physics of that dimension which would mean they expend the energy in that dimension that had been obtained within the first dimension. Supposing multiple dimensions do not share the same output of our dimensional physics but instead hold their own enclosed system yet are regulated by the same fundamental laws. Would it be safe to say the atom holds the properties of perpetual motion because of quantum leaping? Now I agree in our dimension perpetual motion goes against our laws of physics because it states that the natural digression or expenditure of energy can be over come. But what if it is possible to achieve through quantum leaping? Sharing energy with the other dimension in which case the electron holds an equal "momentum"????? in other words if it expended the energy in our dimension's system of physics it would essential "slow down" the electron but instead it expends the energy in the other dimensions and is then reinstated into the first dimension to "regain" its original measurement of energy. In our dimension it would appear perpetual that it never lost energy nor gained any but in essence it would complete the natural laws of physics in the other dimension where we wouldn't see it... Did I make sense? I don't know. Just a thought. I could be wrong. Any statements would be appreciated. please respond reasonably I already stated I am new, if I am off just teach me where I am wrong so I can be corrected. We were all once drooling infants who needed to learn if you put one apple next to the other it makes two apples.... :-)
    Thanks all!
  2. jcsd
  3. Aug 14, 2009 #2


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    I think you will be more productive if you learn more before you speculate. Talking about leaps into other dimensions does not make sense when there are great existing theories (QM) which explain many phenomena successfully.

    You could just as easily speculate about Santa Claus. But that doesn't explain anything, because I already know where the toys under the tree come from.

    I realize you visualize things a certain way, many of us do. Yet QM has defied that kind of visual representation for over 80 years! I would learn about the basics of QM - the HUP, atomic structure (especially electrons), photons, virtual particles, etc. first.
  4. Aug 14, 2009 #3
    Well, it looks to me like you've misinterpreted what a "quantum leap" actually is. It is actually possible to pinpoint the exact position of an electron. However, the Heisenberg uncertainty principle says that the uncertainty in the position multiplied by the uncertainty in the momentum must be greater than or equal to a very small number. So, if the uncertainty in the position is zero, the uncertainty in the momentum must be infinite, thus you can only know the position at the exact moment at which it is measured.

    A quantum leap is something totally different. It describes the sudden transition of a particle from one state to another. The states are usually denominated by "quantum numbers". Classically, these numbers are things like co-ordinates and velocity. Thus 6 numbers (non-integer) are able to describe a classical free point-particle in 3D space (3 position and 3 velocity components).

    In quantum mechanics, the system can be fully described as a superposition of "discrete" or "quantum" base states. These base states are fully described using "quantum numbers". So an electron in the ground state of a hydrogen atom can be described in just 4 numbers (for energy, angular momentum, z-component of angular momentum and spin). If an electron exists in a superposition of these base states, then a measurement on the system will indicate that the electron is in only one of these states. This leads to the Copenhagen interpretation in which the superposition breaks down into just one of the states upon measurement.

    As an example, the electron may be in a superposition of the base state and one of the excited states. If the co-efficients of this superposition (which may be complex numbers) both have equal amplitude, then a measurement on the system with give that the electron is in the base state 50% of the time and in the excited state 50% of the time.

    A quantum leap is the change of an electron from one of these discrete states into another. Since the position of the electron is not defined, we cannot say that the electron "leaps from one position to another instantly", merely that the probability cloud of finding an electron changes instantly.

    I hope that helps clear things up, if only a little bit.
  5. Aug 14, 2009 #4
    This is a question of microscopic vs macroscopic systems. In a microscopic system all processes are reversible. Perpetual motion machines must overcome the friction in the system to continue moving. So there are 3 ways of achieving this:-

    1) Generate free energy, i.e. increase the amount of energy. Conservation of energy is a physical law which forbids this, based upon centuries and centuries of experimental evidence.

    2) Retrieve the energy lost to the surroundings: As most friction eventually ends up as heat, this heat could be used to power the device, however this is forbidden by the 2nd law of thermodynamics, one of the most thoroughly tested laws of physics. Look into work by Carnot and Boltzmann for the pains they go through to prove it.

    3) Remove friction completely: Lubrication can only go so far, but spinning objects in space, left uninterrupted should in theory continue indefinitely. However, I don't think this is what is usually thought of when thinking of perpetual motion machines.
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