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Occam's Razor & Physics

  1. Mar 4, 2013 #1
    Do physicists support Occam's Razor?

    Does Physics support Occam's Razor?

    Do all branches of Physics equally support Occam's Razor?

    Which branches of Physics might tend to support Occam's Razor more, and which branches might tend to support it less?
  2. jcsd
  3. Mar 4, 2013 #2
  4. Mar 5, 2013 #3
    Alright, would you say that fundamental physics concepts like "Wave-Particle Duality" or "Quantum Fuzziness" are truly consistent with Occam's Razor? There seems to be a lethargy in trying to definitively pin down conflicting perspectives to reconcile them with one another. Does the sharp edge of Occam's Razor have its limits?
  5. Mar 5, 2013 #4


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    Are you trying to ask a question or make a point? Occam's Razor doesn't have a sharp edge. It's just a heuristic, although a very important one. Indeed, it has played a large role in the formation of the standard interpretation of quantum mechanics.

    The wave-particle duality is "simpler" than the Bohm pilot wave theory, because it doesn't stipulate the existence of unmeasurable position and momenta of the particle, and an ad hoc pilot wave. Quantum Fuzziness is a really hand-wavy term. Better use more clear terms like Heisenberg Uncertainty Principle (HUP). HUP is actually a very parsimonious principle, because it doesn't stipulate more information about a system than is actually measurable. Since we cannot measure both the position and momentum of a particle exactly, Occam's Razor suggests to us that the particle doesn't have an exact momentum and position simultaneously. In fact, this is a simpler situation than specifying that there is an exact momentum and position, but we can't measure it, because the simpler situation requires less information in the model.
  6. Mar 5, 2013 #5


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    What conflicting perspectives? Attempting to stick to the particle or wave view misses the point of QM. Things are neither waves nor particles, they are quantum objects with entirely different rules than we are used to at our scale. Since there are no simpler explanations which also match with observations Occams Razor suggests that this view is true.
  7. Mar 5, 2013 #6
    The usual example is Ptolemey's epicycle theory of the solar system. When the Copernican theory came it wasn't any better at calculating positions, but it was much simpler.

    Relativity is at base quite simple, so it would be pro-Occam.

    The "multiverse" idea is popular in spite of being very much in opposition to Occam.
  8. Mar 5, 2013 #7
    Absolutely. Many people have tried to add many things to those concepts, in order to make them "feel good" and mesh with their own personal intuition. But all that the added ideas and clauses do is complicate the theory while adding no additional predictive or descriptive ability. Per Occam's Razor, those pet ideas get thrown out. What we want is the simplest theory we can get which accurately predicts and describes our observations. Anything added to that theory which does not increase our predictive or descriptive ability is superfluous and gets thrown out, whether it feels good or not.
  9. Mar 5, 2013 #8
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