Dalo

Why I am a determinist Descartes had his treacherous demon that tried to confuse him and lead him astray, and the only certainty Descartes then had was his cogito. Even confusion presupposes thought. Modern physics has taken over the role of the evil demon and confusion is queen (or king?) again. With this huge difference: thought does not help anymore to create a rational world. You may think what you want, Reality does not seem to care. Atoms and photons go through any slit they feel like going through and zombie cats rule. There are many philosophical and metaphysical arguments in favor of determinism. I will give you only one. Non-deterministic models presuppose that matter behaves randomly and that in turn presupposes a minimal intelligence of matter. Before reacting an element of matter would have to choose which line of action it should follow. Should it act like a wave, or like a particle? And how would it choose? If it does not need to choose, then we are still within a deterministic model even if different courses of action are available. A photon or electron acts as a wave in configuration A, and as a particle in configuration B. We may find it strange or even mystifying, but in the end we still have the same Principe of one cause to one effect.

wrong arguments since in those cases the sun is not in the line of sight as the lamps would be.

My point is: when beams are blocked, we get to see the light source, here the sun, in my experiment the (laser) lamps. But please let's not restart the discussion. The authenticity of my previous picture of the sun had raised doubts which I could not take away, not having noted the conditions under which it was taken. So, today, I took another picture of the sun with the same filter. I am sad to say that I believe you.

Taken in the afternoon between 3 and 4 with filter cap normally used with a telescope to observe the sun. As you can see, the sky is completely dark, all the sun rays having been absorbed, leaving only the sun itself.

This is more of an analogy. And the difference is what makes the experiment meaningful in my eyes. By reducing the intensity of the light, the laser lamp (the light source) itself becomes visible, just like the sun through a filter. Remember that when I used the term mini suns for the first time, I assumed that they propagated light in only one direction. This is I think the fifth or sixth time that you, and others, have tried to remind me that light is propagated in all directions, which is an undeniable fact. That is why I am using unidirectional lasers (or lamp with slits). Please stop repeating the same objections over and over again. It looked like my setup was finally clear to you. It is obvious that you do not agree with my prediction. You think an experiment is superfluous. What more could you possibly say that would make me change my mind? I will tell you, hoping that it will all save us time and energy, and protect us from frustration: only an experiment that would prove me wrong will convince me. There is no theory that, at least in principle, could not be falsified by an empirical experiment, how trivial it may seem.

yes I did. But what I mean goes beyond that: the beams are not projected on the screen anymore. Just like in the case of the picture of the sun with a filter. The sky is dark, and only the sun is visible.

No, when you use a gray filter the beams are mostly absorbed and are not visible anymore. Just like when you take a picture of the sun using a so-called sun-filter

when using the filter the beams are not visible anymore, only the light sources. In this sense, it is just like any other scene. Your judgment expresses your confidence in the theory, and there is nothing wrong with that. That does not mean that an empirical confirmation would be superfluous.

I already did, but I will say it again. You have to imagine that the filter is being used, and that the diaphragm is completely open. In such a situation it is to be expected that all five light sources will be visible on the screen. Such a situation is comparable to any other scene being projected through a lens on a screen. Closing or opening the aperture should have no effect on the field of view, and all the five sources will remain visible whatever the aperture. In other words, closing the aperture will have an effect on the number of beams passing through the aperture, but not on the number of light sources projected on the screen. It is of course only an abstract prediction that must be confirmed, or infirmed, empirically. I do not have a full fledged theory to justify my prediction, but I would like to know first what its value is.

When the diaphragm is completely open, five beams pass through the aperture, three when it is closed. My prediction is, when the (neutral) filter is used, five light sources will be projected on the screen, even if the aperture would only let three beams through. I am not a talented artist, and the way the beams are refracted is certainly not realistic.

Not true. I cannot help it if you are unable to read texts without being blinded by your prejudices.

not true. I kept the same model the whole thread. Sometimes I used analogies to clarify what I meant. But if you read my posts carefully you will see that I remained consistent all along. Concerning the 5 laser beams, they are essential to the experiment.

of course. It is now clear where we both stand. I think a further theoretical discussion will not bring up any new facts or make us change our respective mind.

I do not see why. 1) The diaphragm must keep the same position for the whole experiment. 2) the aperture, opening of the diaphragm can be varied. 3) The filter is applied to the source of light, before they enter the lens. There is only one layout, maybe I should have clearly indicated that the one with the diaphragm place on the focal length is completely uninteresting. The diaphragm will therefore have to be at a position where all five beams can pass when it is completely open, and only three beams can pass when it is close. edit: if you still think that a filter should have no effect on the number of sources projected on the screen, with the condition as stated concerning the position of the filter (before the beams enter the lens), then you prediction is exactly the opposite of mine. You may be already convinced that you are right, I would like to see it confirmed by an experiment.

Now you start with the second phase of the experiment. The dimming of the beams with a filter or otherwise. It is obvious that when the diaphragm is completely open, we will see projected on the screen five spots representing the five sources. The question now is: will we still see five sources with the diaphragm at the same position, the one in which it blocked two beams, or only three sources projected on the screen?

From up to down. 1) The first drawing should have a diaphragm as well, open all the way. That would be the initial situation.You could use the third drawing, but then the opening is smaller than the opening of the second drawing where only 3 beams pass through. That would be confusing. 2) The second drawing would correctly show three bright spots on the screen, representing the three beams which have gone through the diaphragm. 3) The third drawing needs to make clear that the lines do not represent the beams (which have been dimmed), but their sources, which I called lamps or mini suns. The five projections on the screen would represent the fact that even though the position and size of the aperture is equal to the previous drawing, where only three beams passed, we can nevertheless see five spots representing the sources. It is therefore imperative that the same position of the diaphragm be used for all situations, the only difference being the size of the aperture and the number of beams going through it. I hope I will not need to confirm once again that a change of aperture does not affect the field of view, but only the number of beams that can pass through the aperture. That is what makes this experiment interesting in my eyes: three beams, five lamps/mini suns. I do not know if the result will be as I predict, that is why I hope to see it done one day, by me, or by somebody else.

Do you even read what has been written, or do you just react to isolated sentences?

This shows your inability to read posts carefully instead of reacting to your own ideas. Filters are needed to reduce the intensity of the beams and show the "mini suns" as objects that can be reflected on a screen. I agree completely that aperture does not change field of view... except in the case of beams. That you ignore this shows how little you have understood my proposal. Denigrating it won't change this fact. If you think it is pathetic to wait for somebody to perform the experiment instead of doing it myself, why don't you do it yourself and prove me wrong once and for all. Put your money where your mouth is. I know I do not have the proper gear to do the experiment in a professional way. Maybe you do, or do not care? After all, it is only $10, right?

agreed. That is why I proposed the experiment. You are changing the premises. We are talking about uni-directional beams, like lasers.

I am sure you know that you cannot observe the sun directly. When you take a picture with a camera the diaphragm is wide open. Imagine that when you preset the diaphragm at, say, f/8, two of the five beams are blocked. Before pressing the button, the image is bright because all beams are let through. Keeping the camera at the same position, you now use a gray filter in front of the beams. Even through the open diaphragm, the scene is much darker. But you can now see all five mini suns. Since the field of view must remain unchanged, you should be able to see all five mini suns, whatever the aperture. But f/8 lets only three beams through when no filter is used. According to your rule, using a filter would change nothing except the amount of light (and therefore the shutter time). That would mean that we should see only three mini sun. Both possibilities are contradictory.

No, you can't see the beams that are blocked. That seems pretty obvious. Imagine 5 small suns which happen to shine in only one direction. Two are blocked by the diaphragm. Only three spots will be visible on the screen. So far I think that we agree with each other. Let us now reduce the intensity of the beams by dimming or by using a gray filter. It would make the suns visible while before all we could see were the beams of light. The question now is: imagine that we are still using the same setup, with the diaphragm at the same position as before, where it let 3 beams through and blocked 2. How many mini suns will be projected on the screen? If it is 3, then we have no discrepancy with the number of beams. If it is 5, then we do have a discrepancy.

Yes and yes. What is not explained, and I am repeating myself, is, considering only the first case (of 5 laser beams parallel to one another) how it is possible that even when two beams are blocked, we still can see all 5 lamps from which they originate. Somehow they must emanate rays that go through the diaphragm, while they are at the same time time the sources of the beams that are blocked by the same diaphragm. If that is the case, images of illuminated objects are not projected the same way as images of beams, because if that were the case, we would, under the same conditions, be able to see the same number of beams and lamps. What would make perfect sense is that when beams are blocked, the lamps from which they originate should remain invisible even if we reduce the intensity of the beams. After all, what we are seeing is supposed to be light reflected from the lamps whose beams are blocked.

I still hope somebody will perform the experiment and make a video of it. edit: I don't know who downvoted me, and I really do not care. It is obviously someone who has no idea what the meaning of the experiment is. I think that Strange understands it perfectly, but is victim of what is called cognitive dissonance. That is is why he tries so very hard to make it sound like I am the one who is unclear.

goodbye.

You are playing dumb, and it certainly does not suit you. In one case the image contains 5 elements when the aperture is completely open, in the other case it contains only three after the aperture has been closed. So, even if you want to be a purist, you will have to admit that closing the diaphragm affects what comes through the lens in one way, but not in the other. Also, if my assumption is correct, then we still do not have an explanation for this discrepancy. You may of course withdraw from the discussion at any time.