Why must you insist reality is illusion?

reply to post by sirnex

This is often the result of instruments that, by necessity, alter the state of what they measure in some manner.

This," the observer effect", is NOT, what is making the wave collapse, because AGAIN:

- if the info of the detection is ERASED, the wave pattern continues.

-If the info of the detection is NOT ERASED, the wave collapses.

In BOTH cases the detection has been made.

This proves that the physical act of measuring the particle, the "observer effect", is not the reason the wave collapses.

If it was, the wave would also collapse if the info of the detection was erased, but it doesn't.

Get it now?

reply to post by sirnex

The quantum eraser experiment is a double-slit experiment in which particle entanglement and selective polarization is used to determine which slit a particle goes through by measuring the particle's entangled partner.

What are they doing when they manipulate the partner?

They do so to determine wich slit a particle goes through.

They can destroy or restore the interference pattern by manipulating this particular particle.

Yes because when they manipulate the partner, they know what slit the other particle went through, and then the interference pattern is destroyed.

That's what it ultimately says if you look at the whole text.

reply to post by enigmania

This," the observer effect", is NOT, what is making the wave collapse, because AGAIN:

en.wikipedia.org...(physics)

This is often the result of instruments that, by necessity, alter the state of what they measure in some manner.

The observer effect always has a role because the instruments still detect the particles. So, technically your half right. The interference pattern is destroyed or restored due to the manipulation of the entangled partner.

This proves that the physical act of measuring the particle, the "observer effect", is not the reason the wave collapses.

Right, detection doesn't destroy or restore the interference pattern. manipulation of the entangled partner does.

Get it now?

I've gotten it the whole time, the question is... Do you?

reply to post by enigmania

What are they doing when they manipulate the partner?

They do so to determine wich slit a particle goes through.

If only you enjoyed reading. Would save a lot of senseless argument and copying/pasting.

The next progression in the setup will attempt to bring back the interference pattern by placing a polarizer before the detector of the entangled photons that took the other path out of the beta barium chlorate crystal. (Illustration 2) Because pairs of photons are entangled, giving one a diagonal polarization (rotating its plane of vibration 45 degrees) will cause a complementary polarization of its entangled pair member. So from this point on, the photons heading down toward the double slits will meet the two circular polarizers after having been rotated. And when photons enter either circular polarizer "half way off" from their original orientation, the result will be that on each sub-path half will be given one kind of circular polarization and half will receive the other polarization. The end result is that half the photons emerging from each circular polarizer will be "clockwise" and half will be "counter-clockwise." It will then be impossible to look at the polarization of a photon and know by which path it has come. Each component of an original wave-function will interfere with itself. And at this stage the interference fringes will reappear.

Yes because when they manipulate the partner, they know what slit the other particle went through, and then the interference pattern is destroyed.

See above external quote.

reply to post by sirnex

The observer effect always has a role because the instruments still detect the particles. So, technically your half right. The interference pattern is destroyed or restored due to the manipulation of the entangled partner.

No I'm not half right, I'm completely right. I didn't say there was no observer effect at all, I'm saying that the observer effect is not what is making the wave collapse, and I have proven that in my previous posts.

You could say the interference pattern was destroyed or restored by the manipulation of the entangled partner, but only because the result of that manipulation is knowing and not knowing what slit the particle went throug

Next, in an attempt to determine which path the photon took through the double slits, a quarter wave plate (QWP) is placed in front of each of the double-slits that the second photon must pass through.(illustration 1)These crystals will change the polarization of the light, one producing "clockwise" circular polarization and the other producing its contrary, thus "marking" through which slit and polarizer pair the photon has traveled. Subsequently, the newly polarized photon will be measured at the detector. Giving photons that go through one slit a "clockwise" polarization and giving photons that go the other way a "counter- clockwise" polarization will kill the interference pattern.

This is how they manipulate the particles in order to know what slit they went through. When they know, the inteference pattern is destroyed.

The next progression in the setup will attempt to bring back the interference pattern by placing a polarizer before the detector of the entangled photons that took the other path out of the beta barium chlorate crystal. (Illustration 2) Because pairs of photons are entangled, giving one a diagonal polarization (rotating its plane of vibration 45 degrees) will cause a complementary polarization of its entangled pair member. So from this point on, the photons heading down toward the double slits will meet the two circular polarizers after having been rotated. And when photons enter either circular polarizer "half way off" from their original orientation, the result will be that on each sub-path half will be given one kind of circular polarization and half will receive the other polarization. The end result is that half the photons emerging from each circular polarizer will be "clockwise" and half will be "counter-clockwise." It will then be impossible to look at the polarization of a photon and know by which path it has come. Each component of an original wave-function will interfere with itself. And at this stage the interference fringes will reappear.

This is how they manipulate the particles in order to "erase" the info of wich slit they went through, and that makes the interference/wave pattern reappear.

And that's how it is.

reply to post by enigmania

This is how they manipulate the particles in order to know what slit they went through. When they know, the inteference pattern is destroyed.

It is not a function of knowing, it is a function of detection by the instruments. It need not matter if YOU know the actual results. The process can be automated and the same results achieved in both instances of the experiment.

This is how they manipulate the particles in order to "erase" the info of wich slit they went through, and that makes the interference/wave pattern reappear.

BINGO! It is not a function of KNOWING, it is a function of manipulating.

reply to post by sirnex

If only you enjoyed reading. Would save a lot of senseless argument and copying/pasting.

If you only had reading comprehension skills. Like I said to you way back in this thread, we will never be in agreement cause we're on a whole different level.

How's the weather there, by the way?

[edit on 17/9/08 by enigmania]

reply to post by enigmania

If you only had reading comprehension skills.

Really? Now this just bring's us back to me asking you to provide a direct quote of what is leading you to think your personal knowledge of the results has any bearing on the outcome of the experiment.

Oh right .... it doesn't explicitly say that ... I forgot you explained that to me more than once already! My bad.

reply to post by sirnex

So, under conditions where the double-slit part of the experiment has been set up to prevent the appearance of interference phenomena (because there is definitive "which path" information present), the quantum eraser can be used to effectively erase that information.

This says that if there is definitive "wich path" information available, the interference/wave pattern is destroyed.

So apparently, the knowing of wich path is destroying the wave.

A variation of this experiment, delayed choice quantum eraser, allows the decision whether to measure or destroy the "which path" information to be delayed until after the entangled particle partner (the one going through the slits) has either interfered with itself or not. Doing so appears to have the bizarre effect of determining the outcome of an event after it has already occurred.

Again the "wich path" information.

Giving photons that go through one slit a "clockwise" polarization and giving photons that go the other way a "counter- clockwise" polarization will kill the interference pattern.

The end result is that half the photons emerging from each circular polarizer will be "clockwise" and half will be "counter-clockwise." It will then be impossible to look at the polarization of a photon and know by which path it has come. Each component of an original wave-function will interfere with itself. And at this stage the interference fringes will reappear.

Again the "wich path" information that is responsible.

Originally posted by Melyanna Tengwesta
We notice only part of our TOTAL REALITY, that’s why the 3D Reality is called Illusion

But it is illogical.

Splitting reality up into different levels could be part of your understanding, but your understanding doesn't make 3D Reality the illusion.

[edit on 2008/9/17 by SteveR]

reply to post by sirnex

BINGO! It is not a function of KNOWING, it is a function of manipulating.

No, because in both cases, the detecting and the erasing, the particles are polarized, and yet the pattern varies between the two.

If the polarisation of the particle for the sake of detection, would destroy the wave function, it would also have to destroy the wave function when the particles are polarized for "erasing".

But it doesn't.

reply to post by enigmania

This says that if there is definitive "wich path" information available, the interference/wave pattern is destroyed.

Your right it does say that there is a definitive(conclusive, unquestionable) 'which path' available. Meaning that it is unquestionably taking one of two possible routes.

So apparently, the knowing of wich path is destroying the wave.

Direct quote please. How does your explicit knowledge of the path have any bearing on the outcome of the experiment.

Mind you, 'which path' is in reference to the two possible routes/slits the particle can take. Hence, which path is the particle taking?

Seriously, if you wanted to effectively used the which path issue as a reasonable argument, then you should have quoted this:

However, what makes this experiment interesting is that, unlike in the classic double-slit experiment, the choice of whether to preserve or erase the which-path information of the idler need not be made until after the position of the signal photon has already been measured by D0. There is never any which-path information determined directly for the photons that are detected at D0, yet detection of which-path information by D3 or D4 means that no interference pattern is observed in the corresponding subset of signal photons at D0.

But, since your not making any effort whatsoever to understand the layout of the experiment itself, you will then not understand why even this isn't an effective argument for which you are trying to say. Sad really.

reply to post by enigmania

If the polarisation of the particle for the sake of detection, would destroy the wave function, it would also have to destroy the wave function when the particles are polarized for "erasing".

I want you to further elaborate on why you think this before we delve deeper into this aspect of the discussion.

reply to post by sirnex


Jeah, so if this "wich path" information doesn't matter, why do they even mention it, especially in that context?

reply to post by sirnex

I want you to further elaborate on why you think this before we delve deeper into this aspect of the discussion.

You say it is all a result of manipulation, in this case polarisation, but the particles are polarised in both cases, particle pattern and wave pattern.

So is the polarisation making the wave collapse? If it is then we should always see the wave collapse in this experiment.

reply to post by sirnex

Mind you, 'which path' is in reference to the two possible routes/slits the particle can take. Hence, which path is the particle taking?

No sh*t Sherlock!

That's the question the whole experiment revolves around: "wich path is the particle taking?"


If this info is insignificant, why are they talking about it?

PS, I'm off to bed now, got to be fit tomorrow to enter the quantum battlefield again, TATA!

[edit on 17/9/08 by enigmania]

[edit on 17/9/08 by enigmania]

reply to post by enigmania

If it is then we should always see the wave collapse in this experiment.

Let's try it one more time. Please explain why you think this before we delve deeper in this aspect of the discussion. Saying it should is not an valid explanation of why it should.

Jeah, so if this "wich path" information doesn't matter, why do they even mention it, especially in that context?

It matters in the context of the experiment because why is the particle seemingly choosing one path over another (which path). It matters because these experiments being conducted bring us closer towards understanding the fundamental aspects of what is going on. If we don't determine why the particle takes a certain path over another path (which path), then we'll never understand why it does so. Why does the particle seemingly appear to behave as both a wave and a particle, that is the root issue of the experiment.

reply to post by enigmania

particle pattern and wave pattern.

Wrong again, and you dare question my ability to comprehend what I'm reading. Tsk tsk...


Polarized meaning clockwise or anti-clockwise. Not particle/wave. Read it again, this time reeeeeealy slowly.

P.S. Have a good night man, hopefully tomorrow we can finally get this over with. I'm actually enjoying the discussion as it's helping me learn more about the mechanics of the experiment in the context of the text given without having to read into it or add outside information to it. That and Bicardi 151 helps alot.


[edit on 17-9-2008 by sirnex]

[edit on 17-9-2008 by sirnex]

reply to post by sirnex

You say it is all a result of manipulation, in this case polarisation, but the particles are polarised in both cases, particle pattern and wave pattern.

You read slowly, what I'm saying is, that when the experiment puts out a wave pattern, the particles have been polarised.

If the experiment puts out a particle pattern, the particles have been polarised to.

So the collapse of the wave pattern is not a result of manipulation, in this case polarisation, cause if it was the wave would always collapse.

reply to post by enigmania

So the collapse of the wave pattern is not a result of manipulation, in this case polarisation, cause if it was the wave would always collapse.

You sure do like redefining this experiment don't you??? I'm going upstairs for the night to finish drinking and relaxing. Why don't you work out how to read. Start with 'See Spot Run', excellent starter book.