The Parable of the Watch

[Dragonfly]

This is not "just the way things are." If the measuring technique is faulty - change it.

That is complete nonsense. The Heisenberg relation is not about some faulty measuring technique, it is a fundamental property of canonically conjugate variables, which have a commutator equal to i h-bar, like the components of the position and the momentum operator. That means that you can never measure those variables at the same time with arbitrary precision, no matter what measuring method you use. Such quantum states just don't have exact values. Even Einstein couldn't circumvent this fact, no matter how hard he tried with his thought experiments, which were all neatly refuted by Bohr.

[Mike11]

The way I understood it, it might help UncleJim to think in this way, is as follows:

Let's say I built a computer that can store only a letter or a number at one time, which being stored depends on whether we ask it for a letter or a number. After giving us the letter or number the machine randomizes the next information thus we don't know what the next information it stores is. This problem is further compounded by the fact that the math involved is suspected by our top minds to be beyond what we are capable of as we think it uses 10 dimensional equations to create the information.

We would open up the processor but there is a problem that I need to switch metaphors for

The processor's electrical system is the system that all other systems are built on top of, it will always be faster than any other system we can make. Being on a ladder trying to count the grains of dirt below, I can climb down but even on the lowest step I'm still to far away to see clearly.

The quantum system is the base of what we know anything we use to examine it will be on the macroscopic level and is going to dramatically change it.

Is that a good analogy guys?

Edited March 10, 2008 by Mike11

[BaalChatzaf]

Is that a good analogy guys?

No. The best analogy is the Heisenberg Microscope gedanken (look it up on wiki). Or better still look up the wiki on the uncertainty principle.

See http://en.wikipedia.org/wiki/Uncertainty_principle. The details of Heisenberg's gedanken can be found there.

The contention between position and momentum is built into nature. It has nothing to do with how cleverly we contrive our instruments.

Ba'al Chatzaf

[tjohnson]

In my one course on QM we learned that if you had a box with one electron in it and you began shrinking it in an attempt to determine it's position you lose information about it's momentum. Also if you have a beam of electrons (cathode ray) you can control the momentum of the electrons very accurately but then you have little information about the position of an individual electron. It's not a math trick, it's physics. Here's a math trick.

3 people check into a hotel and the clerk charges them $30. (must be an old story Afterwards he realizes he overcharged them and gives $5 to the bellboy to take to them. The bellboy keeps $2 and gives them $1 each. So they each paid $9 so 3x9=27 and the bellboy kept 2 = 29. So where's the other dollar?

[Brant Gaede]

In my one course on QM we learned that if you had a box with one electron in it and you began shrinking it in an attempt to determine it's position you lose information about it's momentum. Also if you have a beam of electrons (cathode ray) you can control the momentum of the electrons very accurately but then you have little information about the position of an individual electron. It's not a math trick, it's physics. Here's a math trick.

3 people check into a hotel and the clerk charges them $30. (must be an old story Afterwards he realizes he overcharged them and gives $5 to the bellboy to take to them. The bellboy keeps $2 and gives them $1 each. So they each paid $9 so 3x9=27 and the bellboy kept 2 = 29. So where's the other dollar?

They paid 25 dollars. They gave the house five. The bellboy gave them back three, kept two. Figuring this out they then buggered the bellboy. Gave him twenty, he gave back ten and they did it again and again.

--Brant

[tjohnson]

They paid 25 dollars. They gave the house five. The bellboy gave them back three, kept two. Figuring this out they then buggered the bellboy. Gave him twenty, he gave back ten and they did it again and again.

--Brant

LOL, I left out the buggering part because it was irrelevant The trick is after you say 3x9=27 you subtract 2, not add 2. So they paid $27 of which the bellboy took $2 so $25 for the room. Figures don't lie but liars can figure.

[UncleJim]

The way I understood it, it might help UncleJim to think in this way, is as follows:

Let's say I built a computer that can store only a letter or a number at one time, which being stored depends on whether we ask it for a letter or a number. After giving us the letter or number the machine randomizes the next information thus we don't know what the next information it stores is. This problem is further compounded by the fact that the math involved is suspected by our top minds to be beyond what we are capable of as we think it uses 10 dimensional equations to create the information.

We would open up the processor but there is a problem that I need to switch metaphors for

The processor's electrical system is the system that all other systems are built on top of, it will always be faster than any other system we can make. Being on a ladder trying to count the grains of dirt below, I can climb down but even on the lowest step I'm still to far away to see clearly.

The quantum system is the base of what we know anything we use to examine it will be on the macroscopic level and is going to dramatically change it.

Is that a good analogy guys?

What I'm saying is that if something exists that determines what it is.

To say that something exists but that I don't know what it is, is just fine with me. But to say that something exists but that I'm unable to know that; just doesn't make sense. When I say that something exists then that requires that I know it.

To say that something exists but is so small that being able to know what it is is going very difficult - is one thing. But to say its so small that knowing what it is, is impossible, is an intellectual cop-out.

If it can be known to exist then what it is, is knowable; i.e., its known characteristics are (by definition) measurable.