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Thoughts on perpetual motion.

  1. Aug 5, 2004 #1
    First off, I don’t have a phd, im not a scientist (hehe well im a comp programmer and i know some of them to claim to be scientist) My skills and basic understanding physics, classical and quantum are weak compared to the people that frequent this forum. I actually found this forum while I was searching google about dark matter vs dark energy. Since then I have been reading every post discussion here for about the last month. I must say, these boards hold the most interesting discussion I have ever seen/read anywhere else. I love reading peoples views and ideas.

    When it comes to science/life I look at it with an open mind. Nothing is impossible, the only limit is our own imagination. Although someone’s idea may be proven wrong our ability to create that idea is the truly impressive part of an individual (and mankind) and the successfulness of the human race. Whether it be wrong or right, doesn’t matter.

    There have been many great thinkers that have changed the way we view the world, physics or just simply put, how we perceive things to work. But when someone creates a formula/theory it may work for the time with our current understanding but years later it can either be completely proven completely wrong or simply needs a modifier or constant implied to make it work with our current understanding or to fit with other forumals/theories that seem to work.

    Ok, sorry for the rambling, ill get onto my subject.

    The topic that makes most every scientist cringe. Perpetual motion. Claims of being able to have a self maintaining motion. Although the math doesn’t support the word perpetual cause it creates physical impossibilities. I believe it’s simply the word associated with the action that makes the topic seem so ridiculous that scientist don’t want to touch the subject.

    This is a subject that has been a long time interest of mine. I would love to hear peoples views and ideas on the matter. Think of this first. We already can see motion similar to this in every day life. From the motion of our solar system alone, and our planets for hundreds of millions of year currently orbiting the sun. Although it’s at a large scale we can still see the motion, and we know its been along for a long time and will be around for some time to come. Think about small scale now too. How about matter, in its constant vibration. Isnt that kind of an idea of perpetual motion. Will it last forever, kinda. It will last perpetually in our lifetimes.

    I think peoples biggest problem is the ability to think on a scale other then their physical form. Now we see things working on a big and small scale what can we do to create something similar that will work on a scale we can tangibly see and use?

    The biggest problem I see with many machines of creating possible perpetual motion is the fact that they all really on gravity in some way to create the motion. Could coming up with a self maintaining motion machine be easier if you could build it in the void of space where gravity wont be necessary? Using superconductors in some way? Also, can a motion machine harness the power of the motion and create an energy surplus that can be stored?

    I would really just like to read peoples views and ideas on the subject. I don’t want to hear about impossibilities. Cause it may be an impossibility for our current understanding but what good are you to science if you can simply dream up ways something can work. Or at least come to a absolute understanding on why it cant work and could never work.

    Cheers :smile:
  2. jcsd
  3. Aug 5, 2004 #2
    Hi mapper;

    If you are only interested it discussing the possibilities and not the reasons it will not work, I guess I can't offer much input. At one point in the past, I explored the subject at lenght and now except the fact that at any level within the cosmos, perpetual motion as I understand it, is not possible. But, I must admit, I did learn a few things exploring the subject.

    Good Luck.
  4. Aug 5, 2004 #3
    Hey there
    Consider the power and eternity of wind.
  5. Aug 5, 2004 #4


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    An atom is a perpetual motion machine. The solar system is a perpetual motion machine [almost]. The problem is you cannot extract any energy from the forces that power these systems [electromagnetic, gravity] without taking them to lower energy states. This is the underlying problem with the classic perpetual motion machine concept.. free energy. The total energy of any system, including the universe as a whole, is fixed.

    Think of it as a bank account. You can transfer money from one account to another, but, you cannot increase the amount of money in one account without decreasing the amount of money in another account by an equal amount [conservation of energy]. In fact, due to banking fees, the total amount of money in both accounts is slightly less than it was before the transaction [entropy]. Of course that money is not destroyed, merely diverted to other accounts not even involved in the transaction.
    Last edited: Aug 5, 2004
  6. Aug 5, 2004 #5
    Yes, but wind cant be constant in an area so the motion of an object cannot be moved perpetually. Well it may be constant (slight breeze) but still, to move with enough force our current technology can create enough resistance to get an energy source out.

    Its probably our best method to date with the best ability to advance over the decades. Could also say the same for solar panels too. But i want to discuss different. Something that can be created from scratch using mankind’s innovation.

    For example, in space, a giant Space Tether. 2 synchronous rotating objects bound together by a cable of some kind that creates resistance between the two object at each end. The energy/stress between the two can be absorbed and stored. This is being planed on powering space stations currently. Although not perpetual, wouldnt this be able to sustain itself and produce enough energy to be stored to make feasible? If left uninterrupted wouldn’t this sustain itself forever or till at least the stress snapped the tether?

    Its also been thought, having a tether like that with miles of cable, the base is the earth and the end is in orbit. Wouldnt that be considered perpetual motion. I dont like the term perpetual cause it implies "lasting forever". But would this be able to continue for uncountable years? Also, the expansion of the universe, wouldnt that be perpetual?

    If you could I would actually like help with understanding fundamentally why it doesnt work. I just hate seeing things that exist in nature and think it cant be reproduced in some way form or fashion. Although nothing lasts forever, I think it’s the term perpetual motion is the thing that gets people to not give it a second thought. Some new way of thinking of energy generation and capture is available, and capturing energy from motion and having that sustain itself does not seem impossible to me. Just something I would like to chat about and hear your guy’s ideas on the subject. All in good fun and understanding. :)
  7. Aug 5, 2004 #6
    The expansion of the universe naturally happens through destruction and then rebirth. Perpetual, in my belief, implies 'transformation'.

    If we are able to harness the dynamics that guide 'transformation' I previously mentioned, then I think we may have it. Eternal, Self-sustaining energy cannot be harnessed in itself, only the elements that transform it.

    Harnessing a natural force implies that a non-transformational dynamic is applied to a progressive/transforming one, which results in explosion (outward destruction), or in the case of the universe, implosion (self-destruction).
    Last edited: Aug 5, 2004
  8. Aug 5, 2004 #7


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    The term "perpetual motion" (aka free energy) may be a little bit of a misnomer. A solar panel works as long as the sun is shining, but isn't perpetual motion (power), nor is it "free energy." Perpetual motion refers to a machine built by humans that ouputs more energy than is input. Lately perpetual motion hoaxsters have gotten more shrewd with things like Zero Point Energy, which both exists and if harnessable wouldn't really be perpetual motion or free energy. The hoax is in the idea that it may be harnessable
  9. Aug 5, 2004 #8
    Kinda like my vaccuum cleaner...

    More, more, pleeeze! ?
  10. Aug 5, 2004 #9


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    The problem with extracting energy from 'zero point energy', is inherent with the definition. ZPE is the lowest possible energy state permitted by quantum theory. Since the only way to extract energy from any system is to reduce it to a lower energy state, extracting net energy from ZPE is impossible.

    According to theory underlying the Casmir effect, you can create an even lower energy state by blocking virtual particle creation between two parallel plates in close proximity. A force is then created because more virtual particles are create outside the two plates than between them.

    I think this theory is inherently untestable. ZPE only exists in a pure vacuum. No such state exists in the known universe, much less the laboratory. The Casmir effect is more easily explained as a classical phenomenon. The equivalent of the Casmir effect can be produced accoustically, and even by ships at sea under certain conditions [which has been known since the 1800's].
  11. Aug 6, 2004 #10
    Cool. But then how do you fathom black holes in the universe if it's meant to be an implosive event?
  12. Aug 6, 2004 #11
    The accoustic/sea versions are not Casimir effect, although the principle is the same - it's just applied to different types of waves. The quantum Casimir effect has in fact been confirmed experimentally, and measured with good accuracy. Whether it is possible to harness it to produce work continuously, is still unknown, but I beleive it can be.
  13. Aug 6, 2004 #12
    i have a perpetual motion machine. I can't show it to people or tell anyone how it works or it will EVAPORATE

    scary, no?
  14. Aug 6, 2004 #13


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    Actually, the accoustic Casimir effect very similar and uses much the same math as the quantum version. It has the added advantage of being much easier to test. You may find this interesting


    I don't question the theoretical foundation for the quantum Casimir effect [albeit I left plenty of room to make that inference!] My reservations are on the experimental end. There is no known way to create a test environment where the Casimir effect can be isolated. This necessitates using correction factors that are still controversial [not so much as a few years ago, but, important questions remain unanswered]. A recent paper of relevance is


    The math gets pretty brutal in place, but, still interesting.
  15. Aug 7, 2004 #14
    Does not have the term Perpetual motion has to do with a reference to a meta-physical-system? Is that MPS possible to conceive within our science?(not in the philosophical metaphysical sense).
    For example according to Francis Crick, life has an extraterrestrial origin, but on the other hand, according to the "good science", we, the scientist cannot travel at higher velocities than that of light, so, within the frame of that MPS is it possible to conceive a principle that includes and transcends the second law of thermodymics, that law that makes it impossible that Perpetual motion?
    But a principle in this case must be applied, so in what meta-context would the principle be applied? By whom, not God, precisely?

    Their physical form does not imply mind yet, right? so, I wonder if there exists an intermediate level of reality, not a spiritual reality, but sort of meta-physical reality where that principle could be applied?
    In our mathematical physical representations we have that level that is represented by the complex plane- that plane where quantum phenomena take place- that can include and transcend the space-time continuum, would it be possible to apply that principle, that transcends the second law, by higher minds that could take advantage of that intermediate level in ways not known by us, yet?

    Just some thoughts
    PD: As far as I know the complex plane has not be taken so seriously by our science yet; complex numbers are normally used in a most convenient way.

    Cheers :smile:[/QUOTE]
    Last edited: Aug 7, 2004
  16. Aug 7, 2004 #15
    A closer look at formulae and equations derived from physical laws gave clues as to how nature responds to letting go of its infinite supply of energy.

    Let's start with Einstein's mass and energy equivalence equation, [itex] E=mc^2[/itex]. If nature is really generous with its energy bank then the equation would be [itex] E = m [/itex]. But if energy equal mass, there would be no creation and no big bang and matter never comes into existence.
  17. Aug 7, 2004 #16
    What nature is telling us is that: if we want energy, we have to really work hard to get it, by going to a very small scale such as the interior of the nuclei, or to move very fast approaching the speed of light.

    On the biological point of view, every living thing has to get their supply of energy from food from different sources and frequently almost daily through a cycle of waking (working) and sleeping (resting). There is no such thing as a magic pill that allow one without eating and without sleeping for one whole year and this pill also must contain all the necessary nutrients to support a healthy life.

    The bottom line is that what all living is after is the density of energy. Energy density is defined as energy per unit volume. The more energy that can be packed into a given volume the longer this given volume exist. But the increase of volume is a decrease in energy density and is a sign of decay of the system. So a perpetual motion machine is a machine with constant energy density maintained by decreasing its volume. A zero volume object such as a black hole would have infinite energy density and therefore can live forever or not lived at all.
  18. Aug 7, 2004 #17
    Furthermore, by the Stefan-Boltzmann law, temperature is proportional the time rate of change of energy density.

    [tex] - \frac{dE}{dt} \propto T^4 [/tex]
  19. Aug 7, 2004 #18
    black holes, do they really exist?

    Yes, Antonio, there, you have a real reason why such a thing as a black hole cannot exist. Something wrong, very wrong is going on with that theory that predicted them, such a law of conservation of mass and energy cannot be violated; some scientists claim they have found some ones out there, but are not measurements, observations and conclusions paradigm-determined?


  20. Aug 8, 2004 #19
    Are you saying that we only measure for something that we already know to be there?
    I have not finish reading T.S.K. on the notion of paradigm shift. So excuse me if I have put the question out of context.
  21. Aug 9, 2004 #20
    No, Antonio, what I mean is that our measurements and observations and conclusions depend on the paradigm at the background, i.e., the framework we use to cope reality.
    T.S.K. explains this quite well in pages 119-124.
    If our paradigm rejects the wave nature of energy-matter then it will be quite difficult to include them both, and the concept of particle will be then the prevailing one. We will be talking two different languages that do not talk to each other, what, T.S.K called the incommensurability of paradigms

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