I Curious about an idea of a modified polariser to send signals with QE

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The discussion revolves around the concept of using a specially modified polariser to send signals through quantum entanglement, specifically by altering measurement outcomes from a 50/50 ratio to a 52/48 ratio. Participants debate whether such a polariser could enable Alice to signal changes to Bob without traditional communication methods. However, it is emphasized that Bob's results remain random and unaffected by Alice's polariser changes, as correlations only emerge when comparing both their results post-measurement. The conversation highlights the limitations of quantum entanglement in facilitating direct signaling between entangled parties. Ultimately, the idea of using a modified polariser for communication remains speculative and unproven.
tade
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So I'm curious about an idea of using a specially modified polariser to send signals with quantum entanglement, curious to know what's more there is to learn about the idea, for better or worse, its possibilities or impossibilities.

Ok so like in the Bell tests, measuring the spin of an elementary particle, and it has being likened to a coin flip, a 50/50 on either side, heads or tails.

But say we have a specially modified or fabricated polariser which can nudge the measurement results from 50/50 either way to 52/48. As the special polariser has been materially fabricated and synthesized with an anisotropic bias at the molecular level.

And then we are conducting Bell tests, with Alice and Bob monitoring the results at their respective ends. And then if Alice were to swap her polariser from a normal standard one to the special anisotropic one, Bob might be able to tell that she has done so, hence it being a form of signalling.

And I think that a 52/48 shift might be pretty interesting, it can be kinda small or really large depending on the angle you're viewing it from (and using "angle" in a metaphorical sense and not in literal physical one lol)

So I'm just curious and wondering about this idea, and also interested to know if it has been explored before.
 
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tade said:
So I'm curious about an idea of using a specially modified polariser to send signals with quantum entanglement, curious to know what's more there is to learn about the idea, for better or worse, its possibilities or impossibilities.

Ok so like in the Bell tests, measuring the spin of an elementary particle, and it has being likened to a coin flip, a 50/50 on either side, heads or tails.

But say we have a specially modified or fabricated polariser which can nudge the measurement results from 50/50 either way to 52/48. As the special polariser has been materially fabricated and synthesized with an anisotropic bias at the molecular level.

And then we are conducting Bell tests, with Alice and Bob monitoring the results at their respective ends. And then if Alice were to swap her polariser from a normal standard one to the special anisotropic one, Bob might be able to tell that she has done so, hence it being a form of signalling.

And I think that a 52/48 shift might be pretty interesting, it can be kinda small or really large depending on the angle you're viewing it from (and using "angle" in a metaphorical sense and not in literal physical one lol)
All Bob ever sees is a mixture of random outcomes, regardless of what Alice does. Kinda hard to send a message with that.

And yes, you can fashion a setup where there is a bias as you imagine. But that doesn't make any difference. The correlations come only when you compare Alice AND Bob's results. Which requires standard signaling (limited by light speed of course).
 
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DrChinese said:
All Bob ever sees is a mixture of random outcomes, regardless of what Alice does. Kinda hard to send a message with that.

And yes, you can fashion a setup where there is a bias as you imagine. But that doesn't make any difference. The correlations come only when you compare Alice AND Bob's results. Which requires standard signaling (limited by light speed of course).

oh interesting, though, I think that I'm not looking at any correlations, but just Bob observing some changes only from his own end, changes brought about by Alice swapping the polarisers.
 
tade said:
Bob observing some changes only from his own end, changes brought about by Alice swapping the polarisers
Bob cannot observe any change at his end based on Alice making changes at her end. He just sees random outcomes regardless. The only way for Bob to know that Alice has made a change at her end is for Alice to send a signal (at no greater than the speed of light) to tell him.
 
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PeterDonis said:
Bob cannot observe any change at his end based on Alice making changes at her end. He just sees random outcomes regardless. The only way for Bob to know that Alice has made a change at her end is for Alice to send a signal (at no greater than the speed of light) to tell him.

so why doesn't swapping the polarisers lead to a change in the random outcomes
 
tade said:
oh interesting, though, I think that I'm not looking at any correlations, but just Bob observing some changes only from his own end, changes brought about by Alice swapping the polarisers.

Alice sees:
HTTHHTTHHTT

Bob sees:
HTTHHTTHHTT

If Alice changes her polarizer (or doesn't even have one at all!), it doesn't affect Bob's results (as far as can be anyone knows) because they are RANDOM. All Bob ever sees is a random mix of H and T (or 0/1 or U/D or whatever). While you may not care about the correlations, that is what entanglement gives you: a precise estimate of Alice/Bob correlations.
 
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DrChinese said:
Alice sees:
HTTHHTTHHTT

Bob sees:
HTTHHTTHHTT

If Alice changes her polarizer (or doesn't even have one at all!), it doesn't affect Bob's results (as far as can be anyone knows) because they are RANDOM. All Bob ever sees is a random mix of H and T (or 0/1 or U/D or whatever). While you may not care about the correlations, that is what entanglement gives you: a precise estimate of Alice/Bob correlations.

though I was thinking that Bob's end might change from 50/50 to 52/48
 
tade said:
why doesn't swapping the polarisers lead to a change in the random outcomes
Because they are random, and random outcomes can't be controlled.

tade said:
though I was thinking that Bob's end might change from 50/50 to 52/48
No. Bob's ratio of random outcomes only depends on the setting of Bob's polarizer, not on the setting of Alice's.
 
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PeterDonis said:
No. Bob's ratio of random outcomes only depends on the setting of Bob's polarizer, not on the setting of Alice's.

hmm how about say Bob's photons being in entangled correlations with what Alice is doing, her polariser swapping
 
  • #10
tade said:
how about say Bob's photon being in an entangled correlation with what Alice does
If you want to talk about that (very different) scenario, you will need to figure out how to entangle Bob's photon with "what Alice does" and then describe such a scenario so it can be analyzed.
 
  • #11
PeterDonis said:
If you want to talk about that (very different) scenario, you will need to figure out how to entangle Bob's photon with "what Alice does" and then describe such a scenario so it can be analyzed.

so I imagine that the photons are entangled as per usual, though when it comes to the measurements, Alice has the available option to midway-through swap to the special polariser type, which as mentioned earlier, I'm wondering about the possibilities of the scheme, perhaps such as the possibility of creating such a polariser, and of it not breaking the entanglement
 
  • #12
tade said:
so I imagine that the photons are entangled as per usual, though when it comes to the measurements, Alice has the available option to midway-through swap to the special polariser type, which as mentioned earlier, I'm wondering about the possibilities of the scheme, perhaps such as the possibility of creating such a polariser, and of it not breaking the entanglement
This just looks like the same scenario you posed in the OP, which has already been answered.
 
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  • #13
PeterDonis said:
This just looks like the same scenario you posed in the OP, which has already been answered.
hmm, seems like we're stuck in a comments loop :sorry:
 
  • #14
PeterDonis said:
This just looks like the same scenario you posed in the OP, which has already been answered.
tade said:
hmm, seems like we're stuck in a comments loop :sorry:

as i have replied to every single reply so far
 
  • #15
tade said:
hmm, seems like we're stuck in a comments loop :sorry:
tade said:
as i have replied to every single reply so far
That doesn't mean you have added any substance.
 
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  • #16
PeterDonis said:
That doesn't mean you have added any substance.
ok, let's take a look at it again then

well, I'm thinking that maybe you might want to not effectively loop back to #8, of you saying "No.", and me asking "hmm how about.." and then it loops back again, and not sure if it really addresses the question, a "vicious circle"

though not meaning to say that someone is at fault, i think that its just the way that it has ended up.
 
  • #17
tade said:
me asking "hmm how about.."
Read my response to that in #12 again. If you thought you were proposing some different scenario, you were wrong, and you need to go back and think again.
 
  • #18
tade said:
ok, let's take a look at it again then

well, I'm thinking that maybe you might want to not effectively loop back to #8, of you saying "No.", and me asking "hmm how about.." and then it loops back again, and not sure if it really addresses the question, a "vicious circle"

though not meaning to say that someone is at fault, i think that its just the way that it has ended up.
hey @DrChinese maybe let's start from #7 and try it out
 
  • #19
tade said:
hey @DrChinese maybe let's start from #7 and try it out
The response from @DrChinese in post #6 already answers post #7. So does my response in post #8.
 
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  • #20
PeterDonis said:
The response from @DrChinese in post #6 already answers post #7. So does my response in post #8.
oh, from #7 to #6, an instant loop-back

though I'm not sure if it does address, but no worries, i think we can just elaborate and add-on points without much issue
 
  • #21
PeterDonis said:
Read my response to that in #12 again. If you thought you were proposing some different scenario, you were wrong, and you need to go back and think again.
hmm, well, in that case, how about you elaborate on the latter part of #8 referencing on my hopefully elaborations or clarifications of #9 and #11
 
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  • #22
tade said:
how about you elaborate on the latter part of #8 referencing on my hopefully elaborations or clarifications of #9 and #11
I don't think you quite understand: there are no "elaborations or clarifications" in your posts #9 or #11. Nothing you say in those posts changes my response in post #8 at all. You might want to go re-read that response again and again until its meaning sinks in. I don't think you have fully realized that meaning. It is very general.

tade said:
i think we can just elaborate and add-on points without much issue
So far you have had zero success in doing this.
 
  • #23
PeterDonis said:
I don't think you quite understand: there are no "elaborations or clarifications" in your posts #9 or #11. Nothing you say in those posts changes my response in post #8 at all. You might want to go re-read that response again and again until its meaning sinks in. I don't think you have fully realized that meaning. It is very general.So far you have had zero success in doing this.

hey cool it with the shade man lol

and just to clarify, by "at all", do you mean keeping #8 just exactly as it is, and no like, adding some elaboration?
 
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  • #24
tade said:
by "at all", do you mean keeping #8 just exactly as it is, and no like, adding some elaboration?
Yes. The last sentence of post #8 is perfectly straightforward and explicit and needs no elaboration.
 
  • #25
PeterDonis said:
Yes. The last sentence of post #8 is perfectly straightforward and explicit and needs no elaboration.
oh i see, though i feel that despite being straightforward and explicit it could probably benefit more from some elaboration
 
  • #26
tade said:
though i feel that despite being straightforward and explicit it could probably benefit more from some elaboration
What kind of elaboration would you like?
 
  • #27
PeterDonis said:
What kind of elaboration would you like?
tade said:
hmm, well, in that case, how about you elaborate on the latter part of #8 referencing on my hopefully elaborations or clarifications of #9 and #11
oh I'm referring to this
 
  • #28
tade said:
i'm referring to this
I've already responded to that. Rather than keep pointing to prior posts that have not gotten across whatever point you think you are trying to make, try making a new post that tries a different way of getting across whatever point you think you are trying to make.
 
  • #29
PeterDonis said:
I've already responded to that. Rather than keep pointing to prior posts that have not gotten across whatever point you think you are trying to make
Yeah no worries I know you already have, I'm just answering your question
 
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  • #30
PeterDonis said:
try making a new post that tries a different way of getting across whatever point you think you are trying to make.
ok hmm let's see, I'm finding it kinda hard because of how you're so unequivocal, #22, #24, and not sure what I could do, as I've never encountered anything like this before.

but let me try...
 

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