Implications of Quantum Physics

[Kuciwalker]

Originally posted by Dauphin
Getting a coherent beam of pool balls may be a problem.

Diffract them through a slit, silly.

[Dauphin]

You'd need a damn small slit to diffract a pool ball.

[Az]

Azazel, there's no problem with the many-universe interpretation.

However you must realise that the universe which we live in is not determined unltil the moment you make the observation.

Universes in that interpretation do not split except at observation points. So saying "the parallel universe" is naive. As a matter of fact, in that interpretation the interference pattern is the result of us remaining in a superposition of universes.

but why just the universes that are the result of the observation are causing the interference?

[Odin]

The way I learned wave/particle duality is that particles somehow takes every posible path at the same time, creating the electron interference pattern with the double slits.

[KrazyHorse]

Originally posted by Azazel

Azazel, there's no problem with the many-universe interpretation.

However you must realise that the universe which we live in is not determined unltil the moment you make the observation.

Universes in that interpretation do not split except at observation points. So saying "the parallel universe" is naive. As a matter of fact, in that interpretation the interference pattern is the result of us remaining in a superposition of universes.

but why just the universes that are the result of the observation are causing the interference?

Because other choices (for instance what the spin of some other particle in Beijing is) have no effect on the thing being measured...

[KrazyHorse]

Those measurements are independent. Their operators commute....

[TCO]

Originally posted by KrazyHorse
"The observer" is only an interaction with the non-quantum world, George. No need for consciousness or even for the observation to be recorded.

Putting a particle into an eigenstate can be done without anybody ever finding out what the value of the associated observable was originally. Think about putting a single electron in a giant magnetic field (in z direction) in a sealed box. After a longish time you open the box. The magnetic moment of the electron will have aligned with the magnetic field (it will be in an eigenstate of Sz), yet you performed no "observation" in the naive sense on the original spin The axiom goes the other way: it simply says that you can't find out what its Sz is without putting it into an eigenstate of Sz (or energy or any other observable).

And as for the double slit thing, if the electron took a single path without us having to measure it (and we simply didn't know what path that was) then why would there be an interference pattern? If we throw pool balls through slits in the dark and record where they hit we don't get an interference pattern...

I really haven't sat down and thought about it. But the interference thing seems like wave particle duality to me. Is it really a case of the states being intermediate rather than in some distribution?

[KrazyHorse]

It's both. It's more standard to do the problem from wave mechanical sense, but you can also create an observable (left slit or right slit). If you put the path into an eigenstate of the observable (if it travels through a definite slit) there should be no interference as the electron will propagate as a particle from a fixed point (left slit, say) and you will end up with two peaks and no interference pattern. This is observed when you put a detector on the slits to tell you if the particle has gone through (you perform a measurement on the observable left slit/right slit, which puts you into an eigenstate).

There is no local hidden variable interpretation available right now which is consistent with all experimental results...

[Barinthus]

What the bleep do we know? - anybody seen this movie?

[Az]

he way I learned wave/particle duality is that particles somehow takes every posible path at the same time, creating the electron interference pattern with the double slits.

behaves like a wave, hence the "wave-particle duality" thing.

Because other choices (for instance what the spin of some other particle in Beijing is) have no effect on the thing being measured...

None whatsoever?

[Solly]

I get the impression that no-one in physics is intelligent enough to work out the implications, therefore they try to hush up their ignorance with "shut up and calculate" crap.

[KrazyHorse]

I'll repeat my question to you, PA:

what exactly do you think is the dillemma?

[KrazyHorse]

Originally posted by Azazel

he way I learned wave/particle duality is that particles somehow takes every posible path at the same time, creating the electron interference pattern with the double slits.

behaves like a wave, hence the "wave-particle duality" thing.

Because other choices (for instance what the spin of some other particle in Beijing is) have no effect on the thing being measured...

None whatsoever?

Not if your experiment is done right...

[KrazyHorse]

Originally posted by Park Avenue
I get the impression that no-one in physics is intelligent enough to work out the implications, therefore they try to hush up their ignorance with "shut up and calculate" crap.

I don't know a single physicist as dumb as you.

[MRT144]

PA you are the biggest know nothing sack of **** ever