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a reply to: delbertlarson

Do you remember trying to explain to me about 1 particle emits 2 particles when it hits the aether.

Does this make the 2 emitted particles antimatter?

a reply to: blackcrowe

You can think of the aether as two infinite solid seas. One made of electrons, the other made of positrons. You can think of each electron being bound to a positron in the nominal state. Energy can unbind them and thereby free them. That can produce a free electron and a free positron. Hence, both matter and antimatter are produced in the process.

Now that is a simplification. You can also produce other matter/anti-matter pairs out of vacuum.

a reply to: delbertlarson

Brilliant.

Now. Can you work out what's happening here.

A radiating wave is doing something strange the further it radiates.

The results of the particle production experiment are.

1 particle. Followed by

4 particles. Followed by

4 particles. Followed by

4 particles. Followed by

8 particles. Followed by

8 particles.

Accuracy is my problem here now. As i did it by hand.

Is it a drop of magnitude?

I don't understand it. Does it make any sense to you?

originally posted by: moebius

originally posted by: stonerwilliam
a reply to: Arbitrageur

William Reed the phantom of the poles 1906 , Admiral bird expeditions ! and a explorer called Nansen who above the 81st parallel talked of a incredible heat even in Dec

In summer you'll get up to 10°C in the Arctic.

81st parallel is over 600 miles away from the pole.

Please provide actual citation for the "incredible heat even in Dec" claim.

Down load the books i quoted and do the research

a reply to: Arbitrageur

I think if you try to make a "realist" interpretation of events during the quantum eraser experiment, meaning you have absolute time, causality such that events happen after the events that caused them, you will run into some problems, but if you've already written an explanation of this, no need to write it again, you can point me to it and I'll read what you've already written. Or if you haven't explained that yet maybe you can explain it here how a realistic interpretation shows it's not really re-writing the past. The first 10 minutes of this video explains the experiment I'm talking about, one being done in 1999 and some other variations since.

I was stumped by the quantum eraser for a while. The video was difficult for me to come up with a ready explanation for, and I have almost always had ready explanations for quantum phenomena before! So it was a worthy puzzle! I thought that the problem might lie in the details of the experiment so I dug a little deeper.

The video on the quantum eraser left out some key issues. At least if all the experiments are accurately described by this article. The article states that there are polarizers and coincident circuits involved, and as I will show below, that makes it something that we can again understand from a realist footing. Please click on the link for background if my description below isn't clear. Of course, my description below takes things further than the linked article, but the content found by following the link may help understanding as well.

Light leaves a laser and is downshifted in a crystal to produce correlated pairs of photons. One photon from the pair goes toward detector D1. The other goes through two slits and then to detector D2. The issue is whether we see an interference pattern at D2, and how what we see at D2 is affected by what happens to the photon heading to D1.

Case 1 - light hits D1 first; the distance from D1 to the crystal is less than the distance from D2 to the crystal. In this case, the photons heading to D1 impinge upon a filter, either linearly or circularly polarized, and then hit D1. Case 1a - a linear filter - will collapse the wave-function to a linear polarization both for photon 1 (which hits the polarizer) and photon 2 (which gets polarized due to quantum collapse of the entangled state). When photon 2 goes through the two slits and then encounters the circular polarizers it will collapse at the two slits, and also collapse at the circular polarizers, but some of it will remain after all collapses. Hence it will show interference. Case 1b - a circular filter - will collapse the wave-function to a circular polarization both for photon 1 and photon 2. When photon 2 goes through the two slits and then encounters the circular polarizers it will collapse at the two slits, and also collapse at the circular polarizers, but only one of the circular polarizers will let the light through, resulting in no interference. Both case 1a and 1b will use the coincidence circuits to look at only those photons that are correlated with each other. Everything is clear.

Case 2 - light hits D2 first; the distance from D2 to the crystal is less than the distance from D1 to the crystal. In this case, the photons heading to D2 impinge upon two slits, then two circularly polarized filters, and then hit D2. The photon in D2 will first collapse to the entire region of the two slits (or be absorbed at the wall containing the slits). Then, the photon will encounter the two circularly polarizing filters where another collapse will take place. There are three possible collapses at the polarizers. The photon can 1) collapse to the clockwise polarization in front of one slit; or 2) collapse to the counter-clockwise polarization in front of the other slit; or 3) it can collapse so that it has part of its polarization clockwise (in front of one slit) AND part of its polarization counter-clockwise (in front of the other slit). Then that photon will head to the wall. The pattern from photons that collapsed in front of either single slit (possibilities 1 and 2) will not show interference, while the pattern from the photons that collapsed in front of both slits (possibility 3) will show interference. However, without any differentiation, the two slit interference will not be seen, since all three possibilities are continuously happening and this blurs the results. Differentiation comes from using the other photon. If we put a circular polarizer in front of D1, AND THEN USE THE COINCIDENCE CIRCUIT TO SELECT ONLY THE CORRELATED PHOTONS, the selected photons at D2 will give no interference, since we are only counting D2 photons that came from a single slit. (Photons correlated with circular polarization collapsed to the front of one or the other slit.) If we put a linear polarizer in front of D1, AND THEN USE THE COINCIDENCE CIRCUIT TO SELECT ONLY THE CORRELATED PHOTONS, the selected D2 photons will give interference, since this time they have parts that came through both slits. (Photons correlated with linear polarization collapsed to the front of both of the slits.)

So there is nothing impossible to understand here either way. There is no magic. The wavefunction collapses when it encounters something in its path, whether it be a wall, a wall containing slits, or a polarizer. The only thing that gets even remotely mysterious is the instantaneous collapse part, which is not allowed by relativity. But once we return to absolute theory, all is well there too.

While not impossible to understand, it was not easy to understand this. It took a couple of long commutes (radio off), and a few night's sleep to think things over, but I believe the above is what is going on. For readers, please note that it may take several re-readings of the article linked to, as well as re-readings of this post, to work though this. It is rather tricky.

originally posted by: blackcrowe
a reply to: delbertlarson

Brilliant.

Now. Can you work out what's happening here.

A radiating wave is doing something strange the further it radiates.

The results of the particle production experiment are.

1 particle. Followed by

4 particles. Followed by

4 particles. Followed by

4 particles. Followed by

8 particles. Followed by

8 particles.

Accuracy is my problem here now. As i did it by hand.

Is it a drop of magnitude?

I don't understand it. Does it make any sense to you?

I don't follow what you write above. A radio antenna does have its magnitude drop off with distance of course. That's why you lose the signal as you drive across country.

a reply to: delbertlarson

I understand you don't follow. I never described the experiment.

I wondered if it fit the math.

It looks like loss.

But at stages. Why would it be like that?

a reply to: delbertlarson


You might find his idea interesting linking the person to the experiment through entanglement.

a reply to: delbertlarson


You might find his idea interesting linking the person to the experiment through entanglement.

Thanks. That is the video Arbitrageur asked me about, leading to the explanation in my post above.

I believe there is an objective reality, and that quantum results follow when wavefunctions interact with other wavefunctions. No conscious observer is required, in my view. (A discussion of this issue is mentioned near the 2 minute mark in the video.) Instantaneous collapse is required in my way of looking at things, and that is what calls into question relativity. The video deals with instantaneity a bit at the 9 minute mark. I am on the side of a physical wavefunction.

I am happy you posted the video again, since I've watched it again, this time with the understanding I came to in my above post. I see differences between the video and this article which I based my above post on. In the article there are no partially transmitting mirrors, such as those in the video. However, since the article does not use the mirrors, and since the article includes important facts about the polarizers and coincidence circuit, the article is much better to explain than is the video - the video leaves some important things out!

I believe that now that the article is understood, so will be any similar experiment using partially reflective mirrors. However, the use of coincidence circuits and any polarizers would be needed to be identified in order to fully understand what is going on.

a reply to: delbertlarson

Sorry. I sidetracked myself with my last question.

Back to other matters.

If matter and antimatter were represented by odds and even numbers.

To describe an odd number as having symmetry. How?

You can always find your position with odd numbers by choosing the central number. Each side of you to the left and right are now symmetrical.

Now. If you remove the middle number. which was an odd number. You have an even number to your left in descending order. And. an even number to the right in ascending order.

Those 2 even numbers are antimatter.

The next 2 numbers to the side of them are odd numbers. Matter one descending and one ascending. And, so on.

Maybe other matter is represented by ascending and descending numbers.

With even numbers. You have no true position except by a half integer.

If you position yourself in front of an even number. There is no symmetry. Your always left with more numbers to either the left or right.

a reply to: delbertlarson
This is a disappointing answer but not surprising because you seem to miss details that seem obvious to me, like when you suggest Feynman is not talking about gravity when his finger is on the blackboard pointing to the gravity equation.

In this case the video I posted linked to the actual scientific paper on the experiment performed in 1999 that it's talking about, but, I wanted to make absolutely, positively sure you couldn't possibly miss the link to the details of the actual experiment, so I posted a link to it right in the thread, but you still missed it and used a Wikipedia article instead on a different, simpler version of the experiment which is missing the key part, the delayed choice. In fact if you had reviewed that Wikipedia article closely it also refers to the delayed choice quantum eraser in the "See also" section, and it even has a link to the same 1999 preprint for that experiment I put in my post for you as reference #4.

Also there are huge warnings on that page about the article not meeting Wikipedia standards, which even if it met Wikipedia standards, I would still think you would prefer to refer to the actual paper on the actual experiment rather than some Wikipedia interpretation, which in this case it's not even discussing the same experiment but one missing a section of the experiment.

The "rewriting the past" comes into the picture with delayed choice, though under the Copenhagen interpretation it's just part of the "quantum weirdness". It's only rewriting the past if a realist interpretation is attempted, as far as I can tell, and well you completely missed the boat on the "delayed choice" part, despite my best effort to remove any possible ambiguity by linking to the paper on the experiment. I admit however that the names are somewhat confusingly similar perhaps to people unfamiliar with the experiments, but this doesn't explain how you missed the link.

a reply to: blackcrowe

Time is on the curve of the wave.

Number a curve with an odd number.

Start at the central number.

Work with odd numbers.

Remove an amount of odd numbers from centre.

You will be left with a gap. And, the two numbers each side of gap will be matter particles.

The size of particle is determined by how many amount points it has.

On the numbered curve. You can see all the matter particle pairs and the antimatter pairs.

Because it's on a curve. It has time included in it too.

a reply to: Arbitrageur

How does this Construct actually Fly and Navigate ? ...........

a reply to: Zanti Misfit

It's remote controlled and it flaps it's wings. And I want one.

a reply to: Phage
It beats the heck out of my rubber band powered version on features but maybe not on price. On that you adjust the tail which is attached via something akin to a friction fit ball joint, for either level flight, making big circles, or climb, stall and dive, etc, but no steering once you let go of course.

I wonder how long the battery lasts on that one; the rubber band model doesn't fly very long, but the rubber bands are pretty big so they can store a surprising number of twists. At least they did when they were new, but I haven't flown it in years so they probably would break now.

originally posted by: Phage
a reply to: Zanti Misfit

It's remote controlled and it flaps it's wings. And I want one.

Gee , Your Smart Mr. Bootae , but I want it too................)

a reply to: Arbitrageur

Thanks for bringing my attention to the fact that I should have devoted my thoughts to the published quantum eraser paper rather than the simpler experiment. I generally opt for the simpler things first, as often they are the easiest to understand, but as you say, in this case it left something important out. So I've now given the published paper a fair amount of thought, but I need more time before I should post on it.

On that Feynman video, I just heard in his words something different than what you did, despite where his finger was pointing. I followed up to explain this once before, and still you bring it up again, so apparently a misunderstanding remains. I believe you and I just have different views on this, and it may have some relevance to resolve it. I believed, and still do, that he was generalizing what he had shown about one thing - gravitation - to make a point about all of nature's laws. His comment was about "nature's laws" (the plural). I pointed out that the example he discussed did not apply to the dipole force. So we have a different take on this. I do agree it is possible that he may have misspoken, as I do that myself from time to time, but I don't think that was the case, as I will now get into.

Feynman did say things in other venues that linked his thoughts on gravity to those of E&M. For instance, consider this video wherein around the 7 minute mark he discusses patterns in nature and at the 7:12 mark he brings up "the general characteristics of these physical laws" and then states that to illustrate the general characteristics he will use gravitation in most of the lecture. At the 8 minute mark he emphasizes that he will give "an example of physical law" so that we will have "one example of the things about which I am speaking generally". He then states that as the example he will discuss gravitation. He of course does an excellent presentation on gravitation, with a lot of history. At the 37:04 mark, he briefly returns to the issue of generality, but does note (paraphrasing) that it is impossible to pick one example of anything that isn't atypical of the more general thing in some sense. At about the 45:30 point he returns to how gravity relates to other forces, and how gravity relates to other parts of nature, and then remarks that both gravity and the electric force fall off as 1/r^2. At 46:01 he mentions that perhaps gravity and electricity are aspects of the same thing, and discusses this for a few minutes. It is in the sections near 7:12, 37:04, 45:30, and 46:01 that my earlier point is made in this video. My comment now, as it was then, is that dipole forces do not fall off as 1/r^2.

Why do I return to this point about the dipole force? Because, back in my grad school days many years ago, I pondered what Feynman is pondering, and then I came to realize that the magnetic dipole moment of the electron appears to be every bit as fundamental as its charge. So I don't think we should try to generalize from gravity to all other forces. I suspect that my pondering back then might have been initiated by Feynman. While I didn't hear him directly, his views were widely known and followed at the time. It was almost a cult-like following for some.

I also wish to comment that the full video has several attributes I find disturbing. The intro has all the markings of worship. Church bells ringing as the buildings are shown, and then "worshipers" are seen heading in for a service, with the title of the talk superimposed on the video. Next, a fawning introduction by Provost Corson, with excerpts I recall from reading Feynman's autobiography. Then the talk. And then at the end, we see applause, followed by the church bells, accompanied by scenes of the worshipers leaving the service, and then the building against the sky. It's a bit much.

Feynman is, of course, an excellent showman, and he presents his topic in an interesting and compelling way, with dashes of humor that make for an excellent presentation. The discussion of Cavendish around the 42 minute mark indicates that Feynman is keenly aware of the importance of showmanship. Cavendish states his experiment was "weighing the earth", rather than "determining the gravitational constant". There is a lot of good material in the hour, and Feynman clearly was a great physicist, so despite my grumblings I would still recommend that people watch the video as it is quite good. In case someone might miss it (as you know, I occasionally miss things myself unless they are repeated):

Here's the link to the video again.

originally posted by: delbertlarson
My comment now, as it was then, is that dipole forces do not fall off as 1/r^2.

I presume you're talking about something like equation 6.9 below which shows an inverse-cube relationship for a dipole?

George Box said "All models are wrong. Some are useful". It certainly applies to that inverse-cube relationship and Feynman did everything I'd expect him to do to explain how that inverse-cube relationship is "wrong but useful" in George Box terminology. Does the dipole inverse-cube match observation? If you take a simple static electric dipole, it matches observation only as long as the distances involved are large compared to the separation of the charges. What happens if you get closer to the electric dipole? The inverse-cube approximation breaks down, so it's not the right model. What is the right model?

Feynman gives a simple inverse squared equation 6.8 in the Feynman Lectures Vol 2 Chapter 6, which unlike the "wrong" inverse-cubed relationship, doesn't break down at distances close to the dipole.


Here he gives the first clue that the dipole inverse-cube model is "wrong, but useful" when he clarifies that it applies only if you don't get too close to the dipole. Notice that he doesn't make any such exception about the inverse-square formula in 6.8, because the electric dipole is in effect actually two oppositely charged monopoles, each of which has an electric field that follows an inverse-square law.

Then he shows how to take the "correct" fundamental inverse square model in 6.8, and derive a "wrong but useful" inverse cube relationship which is wrong because it breaks down if you get too close to the dipole, as he just inferred. He also takes further measures to try to clarify that the inverse cube model is "wrong, but useful" by saying that it's a "good approximation".




And that is how the "wrong, but useful" "good approximation" inverse cube relationship is derived from the more fundamental inverse square monopole fields of the two charges in an electric dipole. In simpler terms you could say the inverse square relationships of the two electric monopoles is still there, but because they are opposite charges they tend to cancel each other out to a greater and greater extent with increasing distance causing the faster inverse cube drop in the "good approximation" model.

So if I hear Feynman say electromagnetism is essentially an inverse-square phenomenon, I would consider such comments in this context, and given the explanation of Feynman and other physics professors in other textbooks which present these ideas similarly, the fact that dipole forces don't seem to fall off as inverse square is in some sense a mathematical artifact in this electric dipole example of two electric monopoles where fundamentally their electric fields do in fact follow an inverse-square law.

I was watching the video "How the Quantum Eraser Rewrites Time" that someone else posted:

If you scroll to 4:30, he states that the BBO crystal splits a PHOTON into 2 new PHOTONS, each of 1/2 the energy of the original photon. Not sure this is correct. I think A and B are ATOMS that produced 2 PHOTONS which were entangled. Is it possible to split a proton into 2 equal parts? I thought a photon, as a massless particle, could only transmute if it interacted with another particle.

From the paper:
arxiv.org...

A Delayed Choice Quantum Eraser

One proposed quantum eraser experiment very close to the 1982 proposal is illustrated in Fig.1.

Two atoms labeled by A and B are excited by a laser pulse. A pair of entangled photons, photon 1 and photon 2, is then emitted from either atom A or atom B by atomic cascade decay. Photon 1, propagating to the right, is registered by a photon counting detector D0, which can be scanned by a step motor along its x-axis for the observation of interference fringes. Photon 2, propagating to the left, is injected into a beamsplitter. If the pair is generated in atom A, photon 2 will follow the A path meeting BSA with 50% chance of being reflected or transmitted. If the pair is generated in atom B, photon 2 will follow the B path meeting BSB with 50% chance of being reflected or transmitted.