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Quantum Mechanics is a set of Laws

  1. Mar 31, 2015 #1
    Hi, I know this is a basic question however, I am seeking absolute verification on these two points.

    1) Quantum Mechanics is a set of Laws.
    2) Laws only describe what we see. Theories give us the reason behind them.
  2. jcsd
  3. Mar 31, 2015 #2


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    Usually people don't use the terms with such strict definitions. One has to read in context.
  4. Mar 31, 2015 #3
    Would there be a case example in which a Law is not only describing observable facts, or A Theory not just trying to give a reason behind an observation(s)?
  5. Mar 31, 2015 #4


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    Special theory of relativity doesn't tell you the "reason behind" all of it postulates. They are just there as the starting point.

    Just on that alone, your categorization is wrong.

    As has been said, you should never pay too much attention to such labels. If you do, you'll learn all the wrong ideas and impression. Spend more time understanding the physics.

  6. Mar 31, 2015 #5
    I don't really understand what you mean. Are you saying that there is no point to classification? I.E Law/Theory/Hypothesis.

    From my understanding, things can only either Describe an observational fact. Or attempt to make sense of observational facts. Anything else that does not fit in these two categorizations would end up as a Hypothesis. Correct?
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  7. Mar 31, 2015 #6


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    The labeling of something as "law" and "theory" is meaningless in physics. "Hypothesis" has a clearer definition in the sense that it is a starting guess work, i.e. it is not a "law" or "theory".

    I mean, just look at your attempt at differentiating between a "law" and "theory". I've already falsified it. A law doesn't become a theory, or a theory doesn't graduate to be a law. BOTH of them are simply mathematical formalism to describe something. As a physicist, I have never worried about what is called what. Such a thing seems to be only of a "concern" to those outside of physics/science.

  8. Mar 31, 2015 #7
    Then how would you define a law and how would you define a theory, Are you saying that Special Theory Relativity is neither a set of Laws nor a theory?
    Surely the classification seems to have great importance. Since a theory has to agree with a Law.
  9. Mar 31, 2015 #8


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    I don't know to whom it is of great importance. It had never been of any great importance to me. And a theory doesn't have to agree with a "law". Who made up this rule? The BCS theory of superconductivity is one of the most successful theory ever discovered. What "law" did it agree with?

    A theory/law/etc. can ONLY be verified convincingly via experiment. Period. That is the only thing those theories, laws, etc. have to "agree" to.

  10. Mar 31, 2015 #9
    From my understanding BCS theory of superconductivity is a theory because no fundamental law can be proven at this point that correlates physical and electrical parameters of superconductors. We don't fully understand what is the root cause of super conductivity, it is mostly based off assumptions for now. Most high temperature superconductors were stumbled upon coincidentally because we still don't know what to look for. (correct me if I am wrong) Scientists are still trying to find the Law that governs super conductivity.

    If a theory is not based on a Law(s) then what is it? A hypothesis. correct?
  11. Mar 31, 2015 #10


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    Sorry? We don't fully understand the root cause of superconductivity? Are you out of your mind?

    What theory is based on laws?

    Again, you never answered my questions, and you've never addressed the contradiction that I've shown of your point of view.

    Please read this Helen Quinn's essay. Notice that she doesn't distinguish between her using the word "theory" and "law". She switches between the two freely!


    So far, the only person who is concerned and spent valuable time worrying about the difference between "law" and "theory" and how they relate to each other is you. I think I have wasted enough of my time.

  12. Mar 31, 2015 #11
    No I am pretty sure i'm fine, I have a Million dollar question for you, How do you go about finding a higher and higher temperature super conductor? When no one knows the exact causes for something to be superconductive. Most if not all high temperature superconductors were stumbled upon coincidentally because we still don't know for sure what to look for. (correct me if I am wrong) Scientists are still trying to find the Law that governs super conductivity.

    Every theory has to be based off some fundamental Law to some degree. Can you create a theory that is based off nothing, no Fundamental Laws? That would be a hypothesis then.


    So what you are saying is that a theory and a Law is interchangeable...?
  13. Mar 31, 2015 #12
    A theory is a hypothesis with significant experimental backing and is (at least in principle) falsifiable. The difference between a law and a theory is nonexistant, and has more to do with the historical period and the field in which the discovery was made than any fundamental difference between the two.
  14. Mar 31, 2015 #13
    Do you have a reference for these things?
  15. Mar 31, 2015 #14
    I can't think of one Theory in existence that is not based to some degree on at least one or more law(s), can you?
  16. Mar 31, 2015 #15
    That is called an argument from ignorance fallacy: http://en.wikipedia.org/wiki/Argument_from_ignorance
    Do you have an explicit reference that backs up your claims.
  17. Mar 31, 2015 #16
    Fundamentally The definition of a Theory in science is linked to a Law. If a Law can be described as facts gathered through observation. And a theory as a hypothesis with experimental backing as Vagn states, then a theory would be fundamentally linked to a Law logically speaking. My question is, does there exist a Theory that is not based on a law to some degree? If all current known theories are all dependent on at least one or more law to a degree than that is the most logical assumption to make.

    An argument from ignorance would be the opposite. I would be arguing that Theories can exist without Laws because you cannot prove me wrong can you?(even though all known theories known currently are all dependent on at least one or more Law(s).)
  18. Mar 31, 2015 #17
    Again, there is no important difference between a theory and a law. But if you can't accept that answer and somehow think that theories must be based on laws, let me ask you: what are the laws that quantum mechanics is based on?
  19. Mar 31, 2015 #18
    I'm not arguing, I'm simply asking questions because the answer given was not clear and some posts in this thread seem to conflict with each other. So the question still remains.

    From my understanding Quantum Mechanics are a set of laws that is observed in subatomic particles. That is why it is referred to as "The Laws of Quantum Mechanics"
    Quantum mechanics are factual are they not?
  20. Mar 31, 2015 #19
    But I thought the answer was pretty clear: there is no useful distinction between law and theory.
  21. Mar 31, 2015 #20
    Considering how I was the only one here to actually attempt to define the two words directly (also Vagn defining Theory) the answer remains extremely unclear. The only answer I got was not that the distinction was not present, but that the distinction was not useful to a physicist in work.

    It also is not helping when a post directly contradicts a previously said statement. I.E
    Apparently you can switch between Law and Theory freely as if they are the same term, yet here we are having another discussion about why a Theory is based on a Law.

    Contradictions are everywhere.
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