The failure of so-called no-communication theorems

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In summary, the failure of "no-communication" theorems in quantum mechanics raises questions about the assumptions made in these theorems and their applicability to potential faster-than-light protocols. The assumption of entangled systems and the absence of "which path" information may not be appropriate for all setups. The idea of FTL in quantum entanglement is currently impossible due to limitations in classical channels, but a potential solution could be found by modulating quantum states. However, the main goal of research institutions is to survive, making it difficult for scientists to act outside of the established norms and think outside the box.
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The failure of so-called "no-communication" theorems

In what we commonly refer to as "no-communication" theorems of quantum mechanics (QM), we make assumptions which are consistent with QM and with our knowledge of physical systems. But are these assumptions appropriate to a potentially would be faster-than-light (FTL) protocol for physics.
Let's first assume that out there in the mind of some brilliant young physicist (possibly not even born yet) is the real FTL protocol. If this is the case, then we must ask, are the assumptions of no-communication theory correct, and if they are correct are they appropriate to the FTL protocol? Do these assumptions cover all possible setups for such a protocol and show that within all setups there is no allowance for FTL? No.

First of all, most no-communication theorems assume an entangled system is the way to go. But is it though? These theorems are a reaction to the EPR/Bell type thinking. But QM had non-locality before EPR(1935) and Bell(1960's) showed up. QM has always had interference between optical pathways, even if the optical pathways are separated by more than the uncertainty in position, as long as the optical pathlengths differ by no more than the uncertainty in position. Some how the coherent superposition is retained even though the paths are separated by a length longer than the uncertainty. As long as the "which path" information is not present in the preparation.

Hmmm, has any of these so-called "no-communication" theorems made up a rule in QM about "which path" information and then assumed this rule in the setup of the theorem. I think not. To put it bluntly, all no-communication theorems simply use "in the box" type assumptions and then low and behold, there is no FTL communication in the box. But if they venture outside of that box they just might become that great young theorist yet.

In general, al onestone states that it makes no sense to make an assertion about what one "cannot" achieve, because it only expresses the limitations of current theory.
 
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al onestone said:
To put it bluntly, all no-communication theorems simply use "in the box" type assumptions and then low and behold, there is no FTL communication in the box. But if they venture outside of that box they just might become that great young theorist yet.


FTL in quantum entanglement is impossible by definition - an operational definition. So far, we know that the statistical comparison between the quantum states of Alice and Bob must be completed by a classical channel, limited to the speed of light.

If that 3-criteria brain: “brilliant, young, physicist” can figure out how to modulate Alice’ quantum state, there will be no need for a comparison A-B, and hence no need for a classical channel. The signal-to-noise ratio will be high enough for Bob to compare the output with his own memory. I'm sure that even if Bob isn’t proficient in music, he will be able to distinguish Mozart's Symphony No. 40 in his headphones from random quantum noise. As I humbly see it.

However, the main task of a research team, research unit or university is never written down in the charter, statutes or paragraphs. The main task is to survive, and a life outside the box is not compatible with life in the long run.

My experience is that many scientists think outside the box too, but we can’t act outside the box. That’s the difference. I highly recommend that 3-criteria brain to make his academic career in the box, but silently do his secret experiments in the garage, funded by the rich uncle.
 

What are "no-communication theorems" in science?

"No-communication theorems" refer to mathematical theorems that describe the limitations of communication between two distant parties. They are commonly used in the field of quantum mechanics to understand the behavior of particles in different locations.

Why are "no-communication theorems" important in science?

These theorems help us understand the fundamental principles of quantum mechanics and how particles behave in different states. They also have practical applications in fields such as cryptography and quantum computing.

What is the main finding of "no-communication theorems"?

The main finding of "no-communication theorems" is that it is impossible to transmit information faster than the speed of light, even through quantum entanglement. This is known as the principle of causality and is a fundamental concept in physics.

What are some real-world applications of "no-communication theorems"?

One of the main applications of "no-communication theorems" is in quantum cryptography, where they are used to ensure secure communication between parties. They are also relevant in the development of quantum computing technology.

What are some limitations of "no-communication theorems"?

While "no-communication theorems" are widely accepted and have been extensively studied, there are still some limitations and open questions surrounding their application. For example, they do not fully explain the behavior of particles in extreme conditions such as near black holes or in the early universe.

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