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# Is a rope a correct analogy of light for understanding what is the polarization?

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I want to understand the idea of the CHSH experiment, and for this I need to understand what the polarization of light is. When light passes through a polarizer, a slightly strange process occurs: if you put two perpendicular polarizers, then the light will not pass through them, but if you put another polarizer between the first two ones at an angle of 45 degrees, then the light will again begin to pass through.

I have heard that a rope is the model for these phenomena. You can start up a linear or circular wave through a rope. If you pass the rope through a slot, then the circular wave will turn into a linear one. If you put two perpendicular slots, then the wave will not pass; but if one more slot is placed between them at an angle of 45 degrees, then again part of the wave will pass. This illustrates that the slot, like the polarizer, “not only absorbs but also rotates”, I hope you understand what I mean. Is this correct?

I want to program a mathematical model that describes a polarizer for light or a slot for a rope, and so far I still don’t understand how to set a diagonal slot in this model. The point is obvious that if the vector [X=1;Y=0] is absorbed by the gap [1;1], then in the basis of this gap one of the components in the vector is set to zero, and in the original basis the component Y does not decrease, but increases, as the vector [1;0] is projected onto [1;1]. That is, as I understand it, one can say that "quantum magic is a consequence of mathematical magic" - in two-dimensional space, when a vector is absorbed, its individual components can increase. Is the written correct?

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Think of polarity as a constant lift, that’s not necessarily the same as the direction it’s going, what is holding it together is favoring a certain direction. Mostly only photons with 90 degree polarity pass through, but it’s also likely that some with a 45 degree polarity will go through with them. A perpendicular filter behind this 90 degree filter won’t have any light go through both, but placing a 45 degree filter between them lets light through all three filters. The light reflects off the third filter because it’s polarity is 90 degrees off, but when it passes back through the 45 degree filter it’s polarity is perturbed and so the gravity it makes going in reverse time replaces it’s polarity when it was at the third filter, allowing it to go through.

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14 hours ago, JeffreysTubes8 said:

Think of polarity as a constant lift, that’s not necessarily the same as the direction it’s going, what is holding it together is favoring a certain direction. Mostly only photons with 90 degree polarity pass through, but it’s also likely that some with a 45 degree polarity will go through with them. A perpendicular filter behind this 90 degree filter won’t have any light go through both, but placing a 45 degree filter between them lets light through all three filters. The light reflects off the third filter because it’s polarity is 90 degrees off, but when it passes back through the 45 degree filter it’s polarity is perturbed and so the gravity it makes going in reverse time replaces it’s polarity when it was at the third filter, allowing it to go through.

Your reply is not clear for me, maybe your English is not good enough (I am not native too). Can you explain the idea with the reverse time in other words?

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5 hours ago, Spathi said:

Your reply is not clear for me, maybe your English is not good enough (I am not native too). Can you explain the idea with the reverse time in other words?

Google retrocausilty interpretation of Shrodinger's cat and quantum eraser

Edited by JeffreysTubes8
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• 2 weeks later...
On 11/18/2022 at 11:40 AM, Spathi said:

If you put two perpendicular slots, then the wave will not pass; but if one more slot is placed between them at an angle of 45 degrees, then again part of the wave will pass. This illustrates that the slot, like the polarizer, “not only absorbs but also rotates”, I hope you understand what I mean. Is this correct?

This is a pretty good wave model of what light does. In both cases, if there is no friction between rope and slot, some of the amplitude (cos θ) passes through, and the rest (sin θ) is reflected back. It isn't absorbed, at least not in the rope case. Light is often absorbed and not reflected by the filter, but I suppose it depends on the filter material.

The perpendicular case is the same as what you get when the rope is simply tied to a wall. All of the wave is reflected back. Water waves do the same thing when hitting a vertical wall, but they lose energy when encountering a sloped surface like a beach.

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