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Could new physical laws be created for large systems?

  1. Dec 22, 2014 #1
    What i basically mean by this is that at this point in time we have classical and quantum physics, both need a different set of rules to describe their phenomenon due to the size of their appropriate systems why is this and does that mean we could also say the same for immensely large systems such as universal sizes? which would work at the opposite end of the spectrum working under almost certain conditions would this be better described with a new compilation of theories macro-theories if you will or would it still follow classical mechanics?
     
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  3. Dec 23, 2014 #2

    Bystander

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    Anything's possible. Would this true "meta-physics" (true in the sense of being beyond, yet encompassing conventional physical theory/law), be distinguishable from what is currently applied to investigations/observations and predictions of the properties and interactions of matter and energy? No.
     
  4. Dec 23, 2014 #3



    Mathematical explanation is applied to fit observation so to an independent observer only being able to get data from a very far away perspective would only be able to come to conclusions based on their unique observations the same applies to the difference between classical and quantum physics from the perspective of classical physics quantum physics does not need to be observed. If any thought has been given in the subject of mathematical/physical perspectives dependent on the size of the systems under mathematical observation be sure to let me know i'm interested in the connection between quantum and classical physics thus i feel like a hypothetical analysis of the reverse would be of great use
     
  5. Dec 23, 2014 #4

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    You might want to start with "the Ultraviolet Catastrophe."
     
  6. Dec 23, 2014 #5
    hahaha that does raise a very good point please try to bear in mind i'm 15 and will sometimes trip over my own logic, you could come to a conclusion about classical mechanics without analyzing quantum mechanics, that much is true, but that does not say there is no connection at all the connection is in the sudden separation and why that was necessary in the physical development of everything.
     
    Last edited by a moderator: Dec 26, 2014
  7. Dec 23, 2014 #6

    Nugatory

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    We already know that classical mechanics doesn't work at cosmological scales or around very large masses - that's why we need General Relavity.

    However, you shouldn't think of GR or quantum mechanics as creating new physical laws but rather as refining, restating, and generalizing our understanding of what the laws of physics have been all along. QM applied to macroscopic systems predicts classical behavior plus insignificant corrections; GR applied to the solar system predicts classical behavior plus insignificant (almost - Mercury's precession is notable) corrections.

    You might be interested in this essay: http://chem.tufts.edu/answersinscience/relativityofwrong.htm
     
  8. Dec 23, 2014 #7

    DrDu

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    This is quite an interesting topic. There is one fraction, called the reductionists, which say that everything can be explained in terms of a small set of fundamental laws. Other people point out the relevance of "emergent phenomena". Typical examples are phase transitions in solid state physics. It is practically impossible to infer the behaviour of very large systems from the quantum laws describing the compound particles. People argue that quantum mechanics has to be embedded into a larger class of mathematical structures, e.g. C* algebras which allows to consistently describe systems with both quantum and emergent classical degrees of freedom in a unified way.
    A nice read is the following book by Hans Primas.
    http://books.google.de/books/about/Chemistry_quantum_mechanics_and_reductio.html?id=bPTvAAAAMAAJ
     
  9. Dec 23, 2014 #8

    DrDu

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    Also Nobel prize winner P. W. Anderson agues against reductionism in his article "More is different":
    http://www.sciencemag.org/content/177/4047/393.full.pdf
    Laughlin may also be a good reading:
    http://en.wikipedia.org/wiki/A_Different_Universe
     
    Last edited: Dec 23, 2014
  10. Dec 23, 2014 #9
    Thank you so much this has been a personal thought for a long time and to have people giving me such great help in understanding it, is a great privilege, being at such a young age it can be very difficult to express some of the more complex thoughts or ideas i have to my peers, they will either not understand or immediately reject such an idea as being over complex or to showy, once again thanks for the help you give an aspiring physicist great hope for the future.
     
  11. Dec 25, 2014 #10

    CWatters

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    MOND is/was an attempt to modify the laws of gravity at long distances/low acceleration to explain the behaviour of some stars (Some stars appear to move so fast they should fly out of their parent galaxy as there isn't enough visible mass).

    http://en.wikipedia.org/wiki/Modified_Newtonian_dynamics

    Alternative theories such as the existence of dark matter seem to fit better.
     
  12. Dec 25, 2014 #11
    Well, I am not sure if this fits into the category of things you wanted to know. But 'new' physical laws which are at least not easily deducable from the microscopic interactions often emerge when many particles come together and interact with each other, such as in thermodynamics.
     
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