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Perpetual motion

  1. Jun 3, 2004 #1
    Is the cosmos a perpetual motion machine?
     
  2. jcsd
  3. Jun 3, 2004 #2
    sure , if you want it to be
     
  4. Jun 4, 2004 #3
  5. Jun 4, 2004 #4
    My personal opinion is that the cosmos is (not) a perpetual motion machine. I just wanted to get some intelligent feed back. Thanks Dogon
     
  6. Jun 8, 2004 #5
    to have a perpetual motion machine you need work with no heat, right?

    where is the heat going?

    into the other cosmos?
     
  7. Jun 12, 2004 #6
    Shrumeo, I would say you need work with no exchange of energy from outside the system.

    Your questions about "where is the heat going?" and "into the other cosmos?", does no make much sense to me. I'm work under the assumption that the cosmos is total existence and therefore, heat or energy is confined to this one and only cosmos.

    I can try to phrase the question a different way if you are truly interest.

    Thanks for your reply.
     
  8. Jun 12, 2004 #7

    Chronos

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    since the universe appears to be a 'free lunch' [something from nothing], you might be able to make that argument. i dont think the oscillating universe is a good answer. it appears there would be ineffficiences between cycles resulting in it eventually achieiving a state of 'rest'. the big rip concept may, however, has some interesting implications. if expansion tears apart the space time continuum, the entire universe might topologically fold back upon itself into a singularity.
     
  9. Jun 12, 2004 #8
    even little bits of it are in perpetual motion, as in an atom's orbiting electrons
    or will a photon travel forever?

    from our limited time scale anyway, both look like perpetual motion to me
    :redface:
     
  10. Jun 12, 2004 #9
    Hi Chronos,

    I think that sometimes appearances can be deceiving. Since I don't think the cosmos is a perpetual motion machine, then logic tells me that the fundamental force must exist somewhere outside of the cosmos. I have a model that demonstrates how this would work, of course following strict guidelines laid down by our present day theories.

    Thanks for your thoughts on the matter.
     
  11. Jun 12, 2004 #10
    Lets restate the Question? lets define the word Perpetual = to:CONTINUOUS with no Startpoint and no Endpoint. Now define the word Motion as to mean: Dynamical in movement at all locations.

    So I declare that under the perspective interpretation the Universe is in a Perpetual Motion State.

    The definition of Machine I will leave to others :smile:
     
  12. Jun 13, 2004 #11

    Chronos

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    we cannot rely on forces outside of the cosmos. any such force must exist within our reference frame.
     
  13. Jun 13, 2004 #12
    Thank you, Olias,

    I like your description and clarification of the terms used. And I am in complete agreement with your interpretation. So, does this Perpetual Motion State require anything to prevent it from eventually running down?
     
  14. Jun 13, 2004 #13
    The question you pose is complex, I think there has to be caution in what we can know with certainty, for instance I am quite certain that we can never See the whole Universe because of our being contained within, therefore we are limited in a 'total' complete understanding.

    An example is this, if we Gauge 'Perpetual' in the Context of both Relativity and Quantum Mechanics, there are similarities, for instance in Relativity the location from where one observes, gives similar results, leading to a 'Continuous-Perspective' no matter where you are, the Universe looks and behaves as if Universal Laws prevail, you cannot gauge where the Universe begins or Ends, and thefore there can not be a centre or a fixed location within the observabel Universe, Dynamical Motion exists everywhere.

    Likewise in Quantum Mechanics 'Perpetual', or Continuous can mean that you cannot isolate a single Quantity so that is detached enough that you can say with total confidence you know everything about what you are isolating, the more you try to isolate some quantity by reduction, the less continuity exists for part of the isolated system, with the fact of reduction of the sysytem produces dynamical motions in observation, the HUP.

    From both extremes there is no single point where one can equilibirate both perspectives?..it is my belief that the middle ground of Relativity has to meet the middle ground in Quantum Theory, and this is the best we can hope for, it is no point shutting out relativity and just treat quantum theory and consequently other reductional theories such as stringtheories as, the 'whole' fundamental perspective or governing Theory.

    I dont think this is a whole answer to your inquisitive questioning, but then again I believe there can never be a single total answer, a single question by its very nature, can never have a single 'True' answer!

    Your question here:So, does this Perpetual Motion State require anything to prevent it from eventually running down?

    Answer:YES, the state system can be run down by a 'single' veiwpoint, the exclusion of 'other' perspective will limit the system, if I only use QM, then by doing so the system will eventually run down. :rolleyes:
     
  15. Jun 13, 2004 #14

    i think the half life of the proton is something like 10^32 years, so not everything is so permanent
     
  16. Jun 13, 2004 #15
    i was trying to get the point across that the whole subject is nonsense anyway
     
  17. Jun 13, 2004 #16
    Hi Shrumeo,

    I don't except proton decay as fact since all the testing to date have proven unsucessful. More test are in the planning stages. The U.S. goverment has included the testing for proton decay as one of 13 top priorities during this century.

    When I see a thread that does not interest me, I just ignore it and move on to something else. I really don't expect to be in sink with everyone here and i'm comfortable with that. Cheers!
     
  18. Jun 20, 2004 #17

    Chronos

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    10^32 is optimistic. 10^40 is more realistic. there are not enough protons in the solar system to test that. proton decay only works in high energy states.
     
  19. Jun 20, 2004 #18
    While this may be a nonsense subject as shrumeo says, it points out an interesting dichotomy (?) in the laws of physics. There are laws that apply within the Universe, but don't apply to the Universe as a whole. For example, within the Universe, perpetual motion machines are forbidden, mainly by the First Law of Thermodynamics which says that you can't create energy from nothing. However, Special Relativity requires that the vaccuum have a negative pressure equation of state which gives it the characteristic of being a resovoir of unlimited energy (See "Cosmological Physics," by John A Peacock, page 26), kind of an energy out of nothing scenario. So, the Universe itself (the vaccuum) kind of gets around the First Law of Thermodynamics. Also, Special Relativity requires that information cannot travel faster than the speed of light, but, there is nothing that says space-time itself cannot travel at any speed. In fact, the Inflationary Big Bang Theory has space-time expanding at MUCH faster than the speed of light during the inflationary period. Again, the Universe as a whole is exempt from this aspect of Special Relativity.
     
  20. Jun 20, 2004 #19
    Someone once said;

    There are no stupid questions., only stupid answers.

    Did I my make a liar out of this guy? (gal?)
     
  21. Jun 20, 2004 #20
    Which guy/gal are you referring to force?
     
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