[DoctorBeaver (OP)]

Bin liners. They are what debunk QM. No matter how many times I try to tear 1 off the roll & open it, I never get it right. Probability? Forget it... it's a dead cert I get it wrong!  [!]

[DoctorBeaver (OP)]

And tents. They invariably go wrong too.

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Bin liners. They are what debunk QM. No matter how many times I try to tear 1 off the roll & open it, I never get it right. Probability? Forget it... it's a dead cert I get it wrong!  [!]

It's a quantistic prepared state []

[DoctorBeaver (OP)]

Bin liners. They are what debunk QM. No matter how many times I try to tear 1 off the roll & open it, I never get it right. Probability? Forget it... it's a dead cert I get it wrong!  [!]

It's a quantistic prepared state []

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It means that you get the same result every time you performe the same measure.

If you make a beam of silver atoms go through a strong inhomogeneus magnetic field (e.g. near the tip of a pointy magnet), the beam splits in 2. If the field's inhomogeneity is along the vertical axis, one beam goes up, the other goes down.

This effect is attributed to a property of the silver atom's electrons, called "Spin".
So the silver electrons are "Spin UP" in the beam which goes up and "Spin Down" in the beam which goes down (this is, in effect, the Definition of the property called "Spin").

If you take the "UP" beam and perform the same experiment on it, with a vertical inhomogeneus mag. field, you will obtain again an up deflection of the beam.

If you repeated the same (it's the "Spin Measure" of the silver's electrons) for a million times or more, you would always obtain the same result.

That beam is called "Prepared" in the sense that it has undergone an interaction with a magnetic field SO THAT the result of the same measure will always yeld the same result.

So, it's not true that the result of a measure is always indefinite, in QM.

[DoctorBeaver (OP)]

Oooh, I never knew that. Thank you  []