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Quantum Mechanics & movement

  1. Nov 10, 2003 #1
    I was recently studying quatum mechanics and thought of a situation
    quantem mechanics in a way is movement and how movemnt and reality
    go together such as e=mc squared but is it posible that the energy of movement or the velocity if you wish could be altered by another
    energy causing the movement to slow or speed up or stop in isnstances
    please if you get the second and know anything on this subject
    reply to this or if anything i have said is wrong corect me for i have just started studying quantum mechanics and would apreciate the help. thanks
     
  2. jcsd
  3. Nov 10, 2003 #2

    chroot

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    That's sort of a tenuous assertion, but okay.
    Well, E = m c2 is a result of relativity theory, not quantum mechanics. I'm also not sure how "reality" enters the equation, or how it deals with movement. It simply relates mass and energy.
    Of course. Such "energies" are more properly called "forces." You can apply a force to a moving object and slow it down, stop it, or speed it up.

    - Warren
     
  4. Nov 10, 2003 #3
    Reality

    reality falls into this because well what if there was no reality
    then there would be nothing so i supose the question i am asking is
    what type of energy or force could change reality and it's movement
     
  5. Nov 10, 2003 #4

    chroot

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    Re: Reality

    What kind of force could.... change reality's movement? This doesn't even make any sense, I'm afraid.

    - Warren
     
  6. Nov 10, 2003 #5
    why

    why does that not make sense to you???

    why is it not posiable for a force to be able to alter gravity,movement or reality itself???

    "it is primitive to beleive something exists or not exists"

    there is proof sugesting that it is posible but none sugesting the opposite
     
  7. Nov 10, 2003 #6

    chroot

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    Re: why

    Forces certainly alter movement. Forces do not alter gravity. Physics does not concern itself with the word 'reality,' since reality is not easily definable. A physicist would delegate a discussion about the definition of 'reality' to a philosopher.

    - Warren
     
  8. Nov 11, 2003 #7
    Re: Re: why

    forces alter gravity.
     
  9. Nov 11, 2003 #8
    Such as?

    Some forces can oppose the effect gravity has on mass, but I am not familiar with any force that truly alters the forces of gravity, or how it functions. To which forces are you refering?
     
  10. Nov 11, 2003 #9
    the source of all gravity is the stress tensor (well... nonradiative gravity). the stress tensor is force per unit area, therefore the more force is in your system, the more gravity it will "create".

    this applies to any kind of force at all. adding more force to the system will make more gravity.
     
  11. Nov 11, 2003 #10

    HallsofIvy

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    So you are saying that if the gravitational force in given situation increases, then that force "created" more gravity??
    You normally make more sense than that!
     
  12. Nov 11, 2003 #11
    i am saying that forces alter gravity.

    if i push on the wall, i have altered the gravitational field in the vicinity of the wall, by exerting a force.

    do you not agree? was it unclear?
     
  13. Nov 11, 2003 #12
    You have not altered gravity in any way by pushing on the wall.
     
  14. Nov 11, 2003 #13
    Yes, you have, but the effect is extremely small --- unmeasurably small, in this case.

    Amplifying on Lethe's point:

    In Newtonian gravity, the source of the gravitational field is mass density. In general relativity, it is stress-energy, which includes not only relativistic mass-energy density, but also momentum density / energy flux, pressure, stress, and strain. Exerting a force on the wall stresses it, and actually changes the gravitational field produced by the wall by a very tiny amount.
     
  15. Nov 12, 2003 #14
    Very true, but you have not altered the behavior of gravity--you have simply changed the way gravity is affecting the surroundings in that particular situation. Gravity, and how it behaves, has not changed.
     
  16. Nov 12, 2003 #15
    but he has

    by pushing on the wall the force of gravity is increased on the wall
    argo it has been changed so what if you could eliminate force upon a being let's say an energy lowers the amount of force on your body then gravity is no as great on the being therefore if you where going to put it in words reality has been altered and so has movement because the normal rules of reality state that you should have the same constant force of gravity on a being but if that force is changed in the way i described above then the rules of reality have been broken and thus changed so in my original question is there a type of energy that could change the movement of reality the answer is yes
     
  17. Nov 12, 2003 #16
    patern

    quantum mechanics sugest that all forces of energy have a movement patern and that if i swing my arm out straight that my body has a specific energy patern when i do this but if that patern was changed then what would happen to my arm going straight out would it stop speed up or slow down this is my original question also my question was what would it take to change the movement patern of this action
     
  18. Nov 12, 2003 #17
    that I can understand....

    but that not.
    are you saying that the force of gravity on the wall is increased? force exerted by what?
     
  19. Nov 12, 2003 #18
    Keen Observation

    Wolf what if there was no human perspective of reality in an unknown and unmeasurable dimension where timelessness exists. In other words, we see the world as we assume it exists. Can anyone reconcile the fact that life forms, human choice or even intelligence arises spontaneously from inanimate sub-atomic particles?

    Most people think only in the 'box' and see OUR reality.

    Supposition: What if 'we' exist in another form, in a stream of an undefined and unknown ether called 'freewill.' This stream of this unknown coursing through this unseen dimension in a singularity (no past, present or future time) but for a short blip in the this flow, the universe and all we sense becomes reality. We can see with our visual cortex, the solid world we live in with emotion, fear, sight, touch, planets, galaxies, the visible cosmos but a non-reality point of perspective.

    That the 'we' (our personal experience) is a true reality but 'we' in effect have no body and no ability to experience the unknowable Truth. So scientists, cosmologists, theologists, physicists go on their merry way making mearsurements, experiments, formula and theory about something that doesn't really exist.
     

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  20. Nov 12, 2003 #19
    The ideas of reality--what is "real" and what is not, is more a study of philosophy than of science. However, quantum mechanics dictates that indeed nothing is "real" until it is observed. Thus, whatever is observed, by humans or anything, becomes real.
     
  21. Nov 12, 2003 #20
    quantum foam,

    Actually you are somewhat correct in your statement. Reality is necessary for science and philosophy to exist in a symbioic relationship for both to be valid. They are not in opposition as many like to argue with the theories of evolution and creationism.

    Quantum mechanics presents an illusory view of the universe. It conveniently arranges mental constructs into dialectical assertions of pure reason, the type that Imanuel Kant would not accept. Each assertion, or thesis, stands opposed to a contradictory assertion or antithesis. Hegel, on the other hand, accepted contradictions as indicative of the true nature of things. Hegel viewed the thesis and the antithesis as imperfect expressions of a more inclusive synthesis. Karl Marx extended the concept to dialectical materialism. The abstract entities named in the thesis and antitheses of quantum mechanics have no real basis in immediate experience. They are mental constructs that exist by virtue of their dialectical opposite. The mind of man can create mental constructs, but it can not create a real object out of nothing. In the very process by which the mind creates mental constructs of abstract dialectical entities it likewise creates credulity and belief in them. The tendency is to confuse abstract entities with existential entities, because supposedly one can not identify what does not exist.

    Do you believe that Quantum Mechanics theories are valid in
    all parts of the universe or even on the 'otherside' of the universe?

    Quantum Mechanics does appear to answer unknown observations that were previously unexplainable but so did Neuton's mathematics in his time.
     
    Last edited by a moderator: Nov 12, 2003
  22. Nov 12, 2003 #21

    chroot

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    I'm pretty sure quantum mechanics says nothing about the "reality" of anything.

    In any event, this thread is rapidly evolving off-topic. Can we get it back on-topic?

    - Warren
     
  23. Nov 12, 2003 #22
    On the contrary! Have you heard of Schrodinger's Cat? Not only does Quantum Theory describe what is real and what is not, but it also describes multiple realities, and things of the such.

    The definition of reality or "unreality" is most certainly not only described in Quantum theory, but is also an intregral part of the theory itself.

    Back on topic, though...

    I still fail to see how "pushing on the wall," as it was put, actually changes the behavior of gravity itself. I agree that the *effect* of gravity on that wall has indeed changed, but the action (in my opinion) has not changed how gravity fundamentally functions or behaves.
     
  24. Nov 12, 2003 #23

    chroot

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    No, it does not. Quantum mechanics describes the probable outcomes of experiments. There are many ontological interpretations of the theory, but the theory itself does not have anything to say about reality.
    It seems to me that you really don't know anything about quantum mechanics beyond what you've read in paperback novels. Do you actually know anything about the theory?

    - Warren
     
  25. Nov 12, 2003 #24
    Quantum Mechanics & What is Real

    Schrödinger's cat

    Oh contrare. Quantum Mechanics states that until something is actually observed, several alternatives remain unknown. Only afer you look in the box can you tell what is real and what did not happen.

    In 1935 Schrödinger published an essay describing the conceptual problems in QM1. A brief paragraph in this essay described the cat paradox.


    One can even set up quite ridiculous cases. A cat is penned up in a steel chamber, along with the following diabolical device (which must be secured against direct interference by the cat): in a Geiger counter there is a tiny bit of radioactive substance, so small that perhaps in the course of one hour one of the atoms decays, but also, with equal probability, perhaps none; if it happens, the counter tube discharges and through a relay releases a hammer which shatters a small flask of hydrocyanic acid. If one has left this entire system to itself for an hour, one would say that the cat still lives if meanwhile no atom has decayed. The first atomic decay would have poisoned it. The Psi function for the entire system would express this by having in it the living and the dead cat (pardon the expression) mixed or smeared out in equal parts.

    It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a ``blurred model'' for representing reality. In itself it would not embody anything unclear or contradictory. There is a difference between a shaky or out-of-focus photograph and a snapshot of clouds and fog banks.


    We know that superposition of possible outcomes must exist simultaneously at a microscopic level because we can observe interference effects from these. We know (at least most of us know) that the cat in the box is dead, alive or dying and not in a smeared out state between the alternatives. When and how does the model of many microscopic possibilities resolve itself into a particular macroscopic state? When and how does the fog bank of microscopic possibilities transform itself to the blurred picture we have of a definite macroscopic state. That is the measurement problem and Schrödinger's cat is a simple and elegant explanations of that problem.
     
    Last edited by a moderator: Nov 12, 2003
  26. Nov 12, 2003 #25
    The Nature of Gravity

    The problem here is what exactly is gravity by definition. Our consciousness makes us aware of this force but as to its source or origin no one knows.

    We know it is a primal force like energy but that too has no known reason for existence in our observable world.
     
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