Bell's Inequality: GTB+GTD+GLD+SLD >= GLD+GTD

[Lazarus]

Swansont:

I asked about the output of the crystal, but even here you haven't said how the polarization could be determined, and just claimed you could do it. The output photon takes the horizontal polarization path. What was the incoming polarization?

 

Lazarus:

You are right. I am not completely comfortable with how the BBO reacts to rotation of the pulse beam. Most of the descriptions jump from alignment of the pump beam vertically to the CHSH setup with the 2 BBO’s aligned 45 degrees on either side of the pump beam. Then the output is described as horizontal from one of the BBO’s and vertical from the other. Here is an example:

 

 

 

Not only does this say that one of the 2 type 1 BBO’s only generates vertical photons, it specifically mentions that a single BBO has its polarization known. That implies the polarization detected determines which BBO the photon came from in the CHSH experiment.

[swansont]

You STILL haven't answered either question.

[Lazarus]

Swansont:

You STILL haven't answered either question.

 

"We next check that the two SPDC cones coming from the BBOs are completely overlapping by checking the polarization of the light incident on our detectors; if the cones are overlapped properly the total SPDC light cone is unpolarized. "

 

If you think that a flashlight will work then you really need to take a giant step back and learn about entanglement before trying to attack Bell tests. Why do you think flashlight photons would have the same polarization correlation that these entangled photons would?

 

Lazarus:

The difference is the photons from the flashlight are in all 360 degrees of polarization but the photons from the BBO have just two choices of polarization. Which allows determination of the source of a photon.

 

 

 

SwansonT

You tell me what the output will be for input light polarized at 45 degrees.

 

Lazarus:

I am willing to go along with Burton Betchart’s contention that at 45 degrees all the photons from one type I BBO are all polarized at the same angle.

 

However, if Burton’s description is correct it doesn’t matter what I think because the generated photons are not indeterminate.

[imatfaal]

lazarus - do yourself (and us) a favour and buy a physics textbook and learn from that. Downloading papers with likely looking titles and hoping you can glean information is a fool's errand.

[swansont]

 

The difference is the photons from the flashlight are in all 360 degrees of polarization but the photons from the BBO have just two choices of polarization. Which allows determination of the source of a photon.

 

 

Not the way they did the experiment. Which is the whole point, really, and one of the things you're missing. There are lots of ways in which the photons would not be entangled. You don't do the experiment those ways.

[Mordred]

Do add to this, there is also lots of ways to decohere the entangled particles as well.

 

You require the right equipment setup.

[Lazarus]

Swansont:

 

Not the way they did the experiment. Which is the whole point, really, and one of the things you're missing. There are lots of ways in which the photons would not be entangled. You don't do the experiment those ways.

 

Lazarus:

Are you saying that Burton Betchart’s description is not correct?

[swansont]

Swansont:

 

Not the way they did the experiment. Which is the whole point, really, and one of the things you're missing. There are lots of ways in which the photons would not be entangled. You don't do the experiment those ways.

 

Lazarus:

Are you saying that Burton Betchart’s description is not correct?

 

 

Are you saying that reading comprehension is the issue here?

[Lazarus]

Swansont:

Are you saying that reading comprehension is the issue here?

 

Lazarus:

Of course not. Just making sure that you think Burton’s experiment is not a real CHSH type experiment. It seems similar to many descriptions of CHSH.

 

What is the difference between Burton’s and a real CHSH experiment?

[swansont]

Swansont:

Are you saying that reading comprehension is the issue here?

 

Lazarus:

Of course not.

 

I meant your reading comprehension, and I have to disagree, as you seem to be asking non-sequitur questions, and don't respond to questions that are asked (you tend to answer some other question) I have said nothing about Burton Betchart's experiment, and yet you are asking if I said something about it.

 

Just making sure that you think Burton’s experiment is not a real CHSH type experiment. It seems similar to many descriptions of CHSH.

You have only provided a snippet of the paper, and (once again) no link to the paper or book, and since the snippet lacks the publication information, I don't know where it came from. I'm not going to comment on a paper I haven't read. The snippet you provided only describes how to make entangled photons. I don't know what he did with them.

 

What is the difference between Burton’s and a real CHSH experiment?

And you've taken this a step further by apparently asking for an interpretation of some comment I haven't made.

[Lazarus]

The link to the Burton Betchart paper does strange things but you can get to it by putting this in the search:

A Test of Bell's Inequality for the Undergraduate Laboratory

 

This link goes to a similar description of the CHSH experiments by Enrique Galvez. This also says that a single BBO cannot entangle photons.

http://spookyactionbook.com/2016/02/21/faq-how-are-entangled-particles-created-video/

 

--------------------------------------------------------------------------------

 

Here is how a Type I BBO with the pulse beam at 45 degrees works:

 

The BBO treats half the photons as vertically polarized and half as horizontally polarized. All of the photons in one half go through unscathed. Occasionally, one of the photons in the other half splits into two lower energy photons. Both new photons are polarized in the same direction. The two new photons go in different directions. The rest of the photons that do not split also go through unscathed.

 

--------------------------------------------------------------------------------

 

This is a timeline of events in a CHSH experiment:

 

There are 2 BBO’s with one in front of the other. The A BBO is on the side of the incoming pulse beam. The B BBO is one the side of the exiting photons. BBO A is aligned horizontally. BBO B is aligned vertically. The pulse beam is aligned at 45 degrees. There are two detectors to catch the coincident events. The pulse beam produces many photons. A few of the photons are split by one of the two BBO’s and travel in different paths. The pulse beam and the entangled photons are at different frequencies so the pulse beam can be eliminated.

 

The one billionth photon is split by BBO A, The 2 resultant photons are polarized vertically. They are only counted if both detectors are activated.

 

The two billionth photon is split by BBO B. The 2 resultant photons are polarized vertically.

 

The three billionth photon is split by BBO B. On and on we go, randomly seeing vertically photons from BBO A and horizontally polarized photons from BBO B.

 

What is indeterminate here?

[Strange]

The link to the Burton Betchart paper does strange things but you can get to it by putting this in the search:

A Test of Bell's Inequality for the Undergraduate Laboratory

 

 

This link: https://etd.ohiolink.edu/rws_etd/document/get/oberlin1206296667/inline

 

Can't see anything strange about that.

[swansont]

The link to the Burton Betchart paper does strange things but you can get to it by putting this in the search:

A Test of Bell's Inequality for the Undergraduate Laboratory

 

This link goes to a similar description of the CHSH experiments by Enrique Galvez. This also says that a single BBO cannot entangle photons.

http://spookyactionbook.com/2016/02/21/faq-how-are-entangled-particles-created-video/

 

--------------------------------------------------------------------------------

 

Here is how a Type I BBO with the pulse beam at 45 degrees works:

 

The BBO treats half the photons as vertically polarized and half as horizontally polarized. All of the photons in one half go through unscathed. Occasionally, one of the photons in the other half splits into two lower energy photons. Both new photons are polarized in the same direction. The two new photons go in different directions. The rest of the photons that do not split also go through unscathed.

 

So how does the detection of one of the down-converted photons tell you the polarization of the incoming photon? You've not answered this.

 

 

--------------------------------------------------------------------------------

 

This is a timeline of events in a CHSH experiment:

 

There are 2 BBO’s with one in front of the other. The A BBO is on the side of the incoming pulse beam. The B BBO is one the side of the exiting photons. BBO A is aligned horizontally. BBO B is aligned vertically. The pulse beam is aligned at 45 degrees. There are two detectors to catch the coincident events. The pulse beam produces many photons. A few of the photons are split by one of the two BBO’s and travel in different paths. The pulse beam and the entangled photons are at different frequencies so the pulse beam can be eliminated.

 

The one billionth photon is split by BBO A, The 2 resultant photons are polarized vertically. They are only counted if both detectors are activated.

 

The two billionth photon is split by BBO B. The 2 resultant photons are polarized vertically.

 

The three billionth photon is split by BBO B. On and on we go, randomly seeing vertically photons from BBO A and horizontally polarized photons from BBO B.

 

What is indeterminate here?

 

What happens when you detect them with a polarizer at 45º, as they did in the experiment. Can you tell which crystal emitted them? Do the statistics indicate that the polarizations were either horizontal or vertical?

[Lazarus]

Swansont:

 

What happens when you detect them with a polarizer at 45º, as they did in the experiment. Can you tell which crystal emitted them? Do the statistics indicate that the polarizations were either horizontal or vertical?

 

Lazarus:

There are three classes of lies, lies, damned lies and statistics.

The statistician drowned in a lake three feet deep, on the average.

 

There are 2 major logic flaws in the CHSH experiments;

 

First: One BBO cannot produce Quantum Entangled photons. The CHSH assumption is that photons from an independent BBO at a different time can change a photon from the first BBO from a known state to a Quantum entangled state.

Second: The photons reaching both detectors at the same time are in the same state. That means both detectors could be looking at the same photon and the results would not change. The rules for one of the detectors are changed. That can create almost any result.

[swansont]

Swansont:

 

What happens when you detect them with a polarizer at 45º, as they did in the experiment. Can you tell which crystal emitted them? Do the statistics indicate that the polarizations were either horizontal or vertical?

 

Lazarus:

There are three classes of lies, lies, damned lies and statistics.

The statistician drowned in a lake three feet deep, on the average.

 

There are 2 major logic flaws in the CHSH experiments;

 

First: One BBO cannot produce Quantum Entangled photons. The CHSH assumption is that photons from an independent BBO at a different time can change a photon from the first BBO from a known state to a Quantum entangled state.

 

Second: The photons reaching both detectors at the same time are in the same state. That means both detectors could be looking at the same photon and the results would not change. The rules for one of the detectors are changed. That can create almost any result.

Given that QM is probabilistic, you have to use statistics.

 

I'll take the rest of that as a "no", and give up on you ever answering a question. The bottom line is that if the photons really had a defined polarization, you get a different result than if they were entangled. You can either deal wiith that, or repeat your unsubstantiated claptrap again.

[Lazarus]

Thank you for the many helpful comments. I don’t feel my contention that the logic of the CHSH experiments is flawed has been refuted but every one has a right to their opinion and your opinions are certainly valuable and based on a great amount of knowledge.

[imatfaal]

Thank you for the many helpful comments. I don’t feel my contention that the logic of the CHSH experiments is flawed has been refuted but every one has a right to their opinion and your opinions are certainly valuable and based on a great amount of knowledge.

 

Unfortunately, that is because you do not understand enough of the basics to realise when your arguments have been correctly countered.

 

You would be much better off starting with the fundamentals of the physics and maths and learning them - from that position you would understand that much of your posting is so far off the mark that it cannot be easily corrected

[Lazarus]

The problems with the CHSH experiments that I pointed out were not discredited or even addressed. They were brushed off along with snide remarks that imply that I am dumber than the rest of you so there was no point in looking at what I had to say.

 

How can you ignore the ridiculous CHSH assumption to start off with that the photons from one BBO can have their state changed from known to indeterminate by photons at a different time from a completely independent BBO?

 

Come on guys, open your eyes and look at the insane logic of the CHSH.

 

Warm regards,

 

Lazarus

[swansont]

How can you ignore the ridiculous CHSH assumption to start off with that the photons from one BBO can have their state changed from known to indeterminate by photons at a different time from a completely independent BBO?

 

 

Can you distinguish the time difference?

 

To know that, you have to know when the photons are created. Do you? Further, you have to measure the time-of-flight difference. You need to know when you detected the photons and do it to sufficient precision.

 

Run the numbers and explain why this can work.

[Lazarus]

Its like saying Jeter’s batting average affected Babe Ruth’s batting average.

[imatfaal]

Its like saying Jeter’s batting average affected Babe Ruth’s batting average.

 

And what you are posting is like saying that both Jeter and Babe Ruth must be holding the bat the wrong way around because you personally do not understand how they manage to do what they do

[swansont]

Its like saying Jeter’s batting average affected Babe Ruth’s batting average.

Complaining that something doesn't make sense to you and then not addressing the actual physics doesn't make for a compelling argument. You claimed that the photons are time-distinguishable. Fine: prove it. Show that it is so.

[Lazarus]

The whole point of the 25ns window is to insure the one at a time capture of pairs.

[swansont]

The whole point of the 25ns window is to insure the one at a time capture of pairs.

 

 

Yes, but that does not have any effect on your claim that you can distinguish between photons coming from one crystal or the other.

[Lazarus]

If there is a bad assumption in CHSH nothing else matters.