[pie]

I have a quesiton about the double split experiment in which once the electon is detected, its assumed the photon is going through the other side, and the wave function of light turns into a particle wave.

Do this quantim event happen only when the researcher knows of when the electon passed through the hole and was detected, or when the detection is made?

Thought experiment:

What if the 2 split experiment was done and the detector knew what side the electon went through, but the researcher did not know till a week later?

Would the print-out still say wave on it after the detection? or would it change the text on the printed page once the research knew the result a week later?

[pie]

More detail:

If at the moment of detection, the computer printed the result. We would know it would be "particle wave" and if the electon was not detected just as always "wave" printout.

Knowing this, if the researcher found out a week later, and knew the print-out occured a week ago, theory should state that the printed result should read "particle wave" instead of "wave" on the printout.

Also, if one researcher did not know of the result, that person should read "wave" on the print-out, however, when the reseacher who knows the result, the paper should state "wave particle."

My theory is that when both researcher views the one printout it would be a mess of words between "wave" and "particle wave"

[Bo]

hmm i dont really understand your question..., but i can say a few things (if i miss the point, please tell me) (before monday, then i will be in romania and deny the internet )
- What you call a particle wave should be just a (point)particle. A particle wave is still a wave imho..
-the correct spelling is quantum (no i's )
- There are 2 versions of the double slit experiment, one is with photons (light) the other with electrons. Which one do you exactly mean? (actually, the experiment could be done with any particle...)
- The detection doesn't really distinguish between particles and waves. you just meassure an electron. The double slit experiment is to show that also the electron has a wave property. (the particle property is e.g. showed in collision experiments)
- The electron doesn't come through one of the 2 slits. Even if you have a single electron, it goes throug both slits at the same time
- Once detected by a detector, The data of the electron is saved somewhere on a computer. A computer is a system that doesn't suffer from any quantum wave effects. Once the detection is made, the electron is forced in a certain state, and that state is saved.

I hope this clarifies it a bit...
B0

[Freethinker]

As a fun side note, check out this site:

"HotAIR - The Double-Slit Garage Experiment"
by R.R. Bukrey
Physics Department
Loyola University, Chicago, Illinois

We are pleased to report that a classic atomic-scale physics experiment -- the double-slit experiment -- has now been carried out on a macroscopic scale. We have demonstrated the wave/particle duality of a familiar, "everyday scale" phenomenon -- the stream of cars passing through the exit lanes of the Loyola University of Chicago parking garage.
http://www.improb.com/airchives/paperair/volume7/v7i6/doubleslit.html

[pie]

Bo - Yes, a point particle after detection of the electron is detected on either side.

Bo - as you stated: "The electron doesn't come through one of the 2 slits. Even if you have a single electon, it goes through both slits at the same time." - Yes, wasn't this the basic question about wheather light was a particle or a wave?

Once the electon is detected through one hole, would then imply that light is a particle, or point particle.
The problem is that it would change from a wave particle to a point particle once detected.

Now if nobody knew the results of the experiment, then it would remain a wave, and not turn into a point particle until the reseracher knew the results of the experiment, which could be a week later.

Now if the computer had the results stored on the hard drive, it would be wave at the time of experiment, because nobody knew the result. Once he research finds the results, a week later, the results will physically change the data on the hard drive from wave to point particle.

This is why Einstein quantum physics as: Spooky action at a distance, or tangled 3rd pair memory that travels faster than the speed of light. Possibly, the single electon theory, in which there is only one electon that created the universe, and what we experience is the shadow of when the electon pased through the early universe billions of years ago.

This is why that when the electon is cornered, and detected, it has to reappear at that loction to prove the whole universe is real.

Instead of suspecting that the we live in a multiple universe with multiple fracturing into other universes, our universe is more like a movie backlot.

The stars are not real until an actual probe inspects there exsistance, and the distances are not real until a probe travels to the planets. - If its not measured or detected, it does not exsist.

[Uncle Martin]

Pie,
You seem to be confusing the quantum world with the macro world. The copenhagen interpretation of QM is wrong. My living room exists after I close the door on my way to work. Pluto existed before it was first observed through a telescope. A tree does make a sound when it falls in the forest,...even if nobody is there to hear it.

It is called reality, come check it out.

[Freethinker]

There was an interesting program today on National Public Radio's Science Fridays today.

http://www.sciencefriday.com/pages/2004/Jul/hour2_073004.html


"Richard Panek, "The Invisible Century" / Einstein vs Bohr

Is it a wave or a particle, or both, or neither? Well, maybe it depends on who is looking. In this hour of Science Friday, we'll take a new look at an old quantum question about the nature of light. A new experiment has the potential to throw a twist into the foundations of quantum mechanics. We'll find out more. "(See a diagram of the experiment,

http://www.sciencefriday.com/images/shows/2004/073004/AfsharExperimentSmall.jpg


courtesy New Scientist, 24 July 2004, p. 35. http://www.newscientist.com)


Imagine, Dawkins changes 180 on info escaping a black hole and we find a photon to be only a wave or perhaps both at once, but never just a particle. All in a few months.