I Superposition Analogy: Ceiling Fan Spin Beyond 15,000 RPM

[ScienceMike33]

Thank you to the very helpful forum leaders for their aide in comprehending entangled particle detection last week.
With regards to superposition, would an analogy be: (which involves a thought experiment):
a ceiling fan, at rest, has four distinct blades with four known positions.

Superposition implies that a quantum particle is present at all possible spin positions at any given time.
Therefore, would an analogy be: a ceiling fan tuned on not just to full (conventional) speed , but much more than that, to a speed far beyond that (lets just say 15,000 RPM /maybe more?). At that level, the fans themselves become invisible to the human eye and further, the fans are virtually in all positions at the same time? Or taking it a step further, if it were possible, a much higher RPM ? Which also brings up the question of how fast an electron spins?

 

[.Scott]

Superposition is not a rapidly changing set of parameters at all.

It is a system that is in a range of states - either a range of discrete states, a continuous range of states, or a combination.

You could have 20 qubits that together binary encoded all prime numbers from 2 to $2^{20}-1$.
In that case if the "ones" position was measured and found to be zero, then all the other qubits would be measured to show the number "2" (000...0010), the only even prime number.

 

[Nugatory]

With regards to superposition, would an analogy be...a ceiling fan

Analogies are based on similarities to more familiar things; if I understand A then knowing that B is like A may help me understand B. However, quantum mechanics isn't like anything that we're already familiar with, so there aren't many (any?) good analogies for QM phenomena.

The ceiling fan analogy is misleading because it suggests that the four blades are somehow more "real" than the blurry disk, that only the limitations of our measurements stops us from seeing that we're working with blades that have a definite position at any given moment and creates the illusion of a blurry disk. Quantum mechanics is nothing like that.

If you want an analogy for superposition, the best I've been able to come up with (and it's not very good) is:
The direction northwest is a superposition of north and west; "one kilometer north and one kilometer west" and "$\sqrt{2}$ kilometers northwest" are just different ways of saying the same thing. But that doesn't mean that "north" and "west" aren't also superpositions; "one kilometer northeast and one kilometer northwest" is the same thing as "$\sqrt{2}$ kilometers north".

 

[ScienceMike33]

Analogies are based on similarities to more familiar things; if I understand A then knowing that B is like A may help me understand B. However, quantum mechanics isn't like anything that we're already familiar with, so there aren't many (any?) good analogies for QM phenomena.

The ceiling fan analogy is misleading because it suggests that the four blades are somehow more "real" than the blurry disk, that only the limitations of our measurements stops us from seeing that we're working with blades that have a definite position at any given moment and creates the illusion of a blurry disk. Quantum mechanics is nothing like that.

If you want an analogy for superposition, the best I've been able to come up with (and it's not very good) is:
The direction northwest is a superposition of north and west; "one kilometer north and one kilometer west" and "$\sqrt{2}$ kilometers northwest" are just different ways of saying the same thing. But that doesn't mean that "north" and "west" aren't also superpositions; "one kilometer northeast and one kilometer northwest" is the same thing as "$\sqrt{2}$ kilometers north".

'

Thank you..Got it ! So yes, then would this convey that the fan blade follows more of a classic or Newtonian mechanics, and superposition /Quantum mechanics follow different precepts? If that is the case then, stating that entangled particles interact faster than the speed of light or that "spooky action at a distance" occurs faster than the speed of light may be like mixing apples with oranges e.g., space/time as we know it, does not exist in the quantum world.

Each of these mechanics therefore may be describing a different part of reality, each valid in its own right but not able to be interchangeable--and if this is true , would the grand unified theory as it were, not exist?

 

[DennisN]

If that is the case then, stating that entangled particles interact faster than the speed of light or that "spooky action at a distance" occurs faster than the speed of light

There is no experiment that has demonstrated that entangled particles interact with each other (i.e. "spooky action") when they are measured. What entanglement experimentally is, is a measured correlation between particles measured at e.g. different locations. There are however experiments that demonstrate that if there would be an interaction, the "speed of it" would be many times larger than the speed of light:

Yin, Cao et al, Lower Bound on the Speed of Nonlocal Correlations without Locality and Measurement Choice Loopholes (Phys. Rev. Lett. 110, 260407 – Published 26 June 2013)
Paper: http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.110.260407