The Delayed Choice Quantum Eraser Experiment

[emptiness]

If you want a true mind****, read about it on Wikipedia.

It's a modern version of the Double Slit experiment which pretty much destroys the idea that the PHYSICAL act of observation collapses the wave function, and it is completely insane.

[size_of_light]

Mankind would be a lot happier if it simply experienced light naturally instead of hunkering down like obsessed nerds in laboratories trying to pull the fucking thing apart.

The outcome of that wiki article was this: we still don't know what light is.

[emptiness]

Mankind would be a lot happier if it simply experienced light naturally instead of hunkering down like obsessed nerds in laboratories trying to pull the fucking thing apart.

The outcome of that wiki article was this: we still don't know what light is.

Yes, but the most amazing thing is that the measurement is made (or not made) AFTER the wave/particle pattern is made on the plate, and the measurement still determines whether the photon ACTED as particle or as a wave.

[themime]

Yes, but the most amazing thing is that the measurement is made (or not made) AFTER the wave/particle pattern is made on the plate, and the measurement still determines whether the photon ACTED as particle or as a wave.

You may find this of interest.

http://www.bbc.co.uk/radio4/history/inourtime/inourtime_20090305.shtml

Some would have you believe that science can prove where the Universe comes from or how the Quantum Universe works but at best these theories are educated guesses and real scientists know this.

[geewhizz]

If you want a true mind****, read about it on Wikipedia.

It's a modern version of the Double Slit experiment which pretty much destroys the idea that the PHYSICAL act of observation collapses the wave function, and it is completely insane.

NO it does not destroy the PHYSICAL act of observation.............

However, the interference pattern can only be seen retroactively once the idler photons have already been detected and the experimenter has obtained information about them, with the interference pattern being seen when the experimenter looks at particular subsets of signal photons that were matched with idlers that went to particular detectors. The total pattern of signal photons at the primary detector never shows interference, so it is not possible to deduce what will happen to the idler photons by observing the signal photons alone, which would open up the possibility of gaining information faster-than-light (since one might deduce this information before there had been time for a message moving at the speed of light to travel from the idler detector to the signal photon detector) or even gaining information about the future (since as noted above, the signal photons may be detected at an earlier time than the idlers), both of which would qualify as violations of causality in physics. In fact, a theorem proved by Phillippe Eberhard shows that if the accepted equations of quantum theory are correct, it should never be possible to experimentally violate causality using quantum effects,[4] although some physicists have speculated about the possibility that these equations might be changed in a way that would be consistent with previous experiments but which could allow for experimental causality violations

[emptiness]

NO it does not destroy the PHYSICAL act of observation.............

However, the interference pattern can only be seen retroactively once the idler photons have already been detected and the experimenter has obtained information about them, with the interference pattern being seen when the experimenter looks at particular subsets of signal photons that were matched with idlers that went to particular detectors. The total pattern of signal photons at the primary detector never shows interference, so it is not possible to deduce what will happen to the idler photons by observing the signal photons alone, which would open up the possibility of gaining information faster-than-light (since one might deduce this information before there had been time for a message moving at the speed of light to travel from the idler detector to the signal photon detector) or even gaining information about the future (since as noted above, the signal photons may be detected at an earlier time than the idlers), both of which would qualify as violations of causality in physics. In fact, a theorem proved by Phillippe Eberhard shows that if the accepted equations of quantum theory are correct, it should never be possible to experimentally violate causality using quantum effects,[4] although some physicists have speculated about the possibility that these equations might be changed in a way that would be consistent with previous experiments but which could allow for experimental causality violations

Whaa? That isn't what I said.

I said that it destroys the IDEA that physically bouncing things off the original photon somehow physically "collapses" the wave into a particle (which is idiotic, i think, anyway).

Not only that, but they can actually "hit" the photon with a tag, then untag it right before it hits the plate, and it will go back to acting as a wave (while if they don't untag it, it will act as a particle).

Crazy stuff.