Physics Quantum entanglement

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wart101

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So what is this spooky action at a distance?

I consider learning about the realm of quantum reality to be a hobby of mine so whilst I'm not an expert I do try to understand to the best of my abilities, I have spent hours reading journals, blogs, wiki and YouTube video but it all seems like hocus pocus.

Can anyone here explain to me in a non convoluted way what it is?

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Macca225

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So what is this spooky action at a distance?

I consider learning about the realm of quantum reality to be a hobby of mine so whilst I'm not an expert I do try to understand to the best of my abilities, I have spent hours reading journals, blogs, wiki and YouTube video but it all seems like hocus pocus.

Can anyone here explain to me in a non convoluted way what it is?

Sent from my SM-G935F using Tapatalk
Not sure it's possible to explain quantum mechanics in a non convoluted way, but I like this video.
 

Chrizzt

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So what is this spooky action at a distance?

I consider learning about the realm of quantum reality to be a hobby of mine so whilst I'm not an expert I do try to understand to the best of my abilities, I have spent hours reading journals, blogs, wiki and YouTube video but it all seems like hocus pocus.

Can anyone here explain to me in a non convoluted way what it is?

Sent from my SM-G935F using Tapatalk
"If you think you understand quantum mechanics, you don't understand quantum mechanics." - Richard Feynman

I don't have a great in depth understanding of entanglement, which limits my ability to communicate it effectively at a "lay" level (which is also what Feynman was alluding to in the above quote).

But basically it has to do with the fact that quantum systems are described by individual quantised states (and the probability of those states being occupied) as well as the well-known conservation of energy. The basic example is you have a particle with spin equal to zero that decays into two separate particles. The total spin of the system must still be zero, so if one particle has a spin of +1/2, the other MUST have a spin of -1/2.

The idea of entanglement and information boils down to that before you measure the spin of either particle both are only described by the probability of spin. Measuring the spin of one particle collapses the system to an eigenvalue (discrete value) and therefore the instant that you measure the spin of the first particle, the spin of the second particle must correspondingly collapse to the appropriate eigenvalue also (e.g. +1/2 and -1/2, respectively)

A large group of scientists at the time, including Einstein who coined the phrase "spooky action at a distance", were troubled by this concept as it would violate causality, i.e. information travelling faster than the speed of light.

This video gives a pretty good explanation of it all, along with links to related information.
 

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sataris

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"If you think you understand quantum mechanics, you don't understand quantum mechanics." - Richard Feynman

I don't have a great in depth understanding of entanglement, which limits my ability to communicate it effectively at a "lay" level (which is also what Feynman was alluding to in the above quote).

But basically it has to do with the fact that quantum systems are described by individual quantised states (and the probability of those states being occupied) as well as the well-known conservation of energy. The basic example is you have a particle with spin equal to zero that decays into two separate particles. The total spin of the system must still be zero, so if one particle has a spin of +1/2, the other MUST have a spin of -1/2.

The idea of entanglement and information boils down to that before you measure the spin of either particle both are only described by the probability of spin. Measuring the spin of one particle collapses the system to an eigenvalue (discrete value) and therefore the instant that you measure the spin of the first particle, the spin of the second particle must correspondingly collapse to the appropriate eigenvalue also (e.g. +1/2 and -1/2, respectively)

A large group of scientists at the time, including Einstein who coined the phrase "spooky action at a distance", were troubled by this concept as it would violate causality, i.e. information travelling faster than the speed of light.

This video gives a pretty good explanation of it all, along with links to related information.
I also believe Einstein was greatly troubled at the the idea of being able to measure the properties of a system but not know anything about the parts within the system
^ My terrible explanation of what he was talking about :(
 

Ando727

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Thanks for destroying my night of sleep guys! I spent all night watching videos and reading stuff about quantum entanglement and spin equations. I feel both more knowledgeable and infinitely more stupid than I did yesterday...
 

Pie eyed

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Thanks for destroying my night of sleep guys! I spent all night watching videos and reading stuff about quantum entanglement and spin equations. I feel both more knowledgeable and infinitely more stupid than I did yesterday...
Telomeres....
Bose Einstein Condensate....
Uracil, Cytosine, Thymine, Guanine and Adenine.

sweet dreams.
 

Ando727

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Ha, I actually do know something about those. I read a very good science fiction novel that dealt with exactly that. After that, I did a bit more research. Like a lot of concepts, not too hard to get a vaguely qualitative understanding - damn near impossible to understand the equations!
 

H2F

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I admit that I have forever believed in the simulation theory that is now being talked about at the moment from Musk, Greene and others.

Quantum Entanglement to me is proof that you can send information across distances faster than light.

Since we are all information this will be our Warp Drive. Hurry up you dumb arse scientists, I wanna Millennium Falcon.
 

cannot

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Thanks for destroying my night of sleep guys! I spent all night watching videos and reading stuff about quantum entanglement and spin equations. I feel both more knowledgeable and infinitely more stupid than I did yesterday...
So what is this spooky action at a distance?

I consider learning about the realm of quantum reality to be a hobby of mine so whilst I'm not an expert I do try to understand to the best of my abilities, I have spent hours reading journals, blogs, wiki and YouTube video but it all seems like hocus pocus.

Can anyone here explain to me in a non convoluted way what it is?

Sent from my SM-G935F using Tapatalk
did they find an answer yet? ...

its most interesting indeed

Quantum Entanglement to me is proof that you can send information across distances faster than light.
me too

monty python no idea
 

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Total Power

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This thing breaks my brain honestly. The question being how do the particles exchange information instantly despite being several light years away?

https://www.scientificamerican.com/...eins-ldquo-spooky-action-at-a-distance-rdquo/

Quantum physics suggests that two so-called entangled particles can maintain a special connection—even at a large distance—such that if one is measured, that instantly tells an experimenter what measuring the other particle will show. This happens despite the fact neither particle has definite properties until it is measured. That unsettled some physicists, including Einstein, who favoured an alternative explanation: that quantum theory is incomplete, and that the outcomes instead depend on some predetermined, but hidden, variables.
 

Thrawn

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This thing breaks my brain honestly. The question being how do the particles exchange information instantly despite being several light years away?
They don't exchange any information:
The way people get around the idea that entanglement implies instantaneous communication is that no actual information is passed when the entangled particles affect each other. The argument is as follows (using a non-QM example):

Say you agree to send out two beams of light to your two friends who live on opposite sides of the galaxy (you live in the middle). Ahead of time you tell them that if one of the beams of light is red the other will be blue. So you send the blue beam to your friend on one side and immediately she knows that your other friend is receiving a red beam at the same time. Aha! You say, my friends have now communicated at a speed faster than the speed of light and violated relativity, but no real information has been passed between them. You have told both of them at a normal sub-luminal speed about what you just did and that's all. (A way of proving there's no faster than light communication is that you could lie and send them both the same coloured beam of light and they would never know!).
 

Total Power

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Im not sure that the concept of "non-locality" addresses anything it just rewords the problem. Changes of the system still propagate to different points of time faster than the speed of light. Since how the system changes IS dependent on the measurements i think it's perfectly fine to say that there is some level of communication at play.

https://www.livescience.com/56076-entangled-particles-remain-spooky.html

his finding comes from a close look at quantum entanglement, in which two particles that are "entangled" affect each other even when separated by a large distance. Einstein found that his theory of special relativity meant that this weird behavior was impossible, calling it "spooky."

Now, researchers have found that even if they were to scrap this theory, allowing entangled particles to communicate with each other faster than the speed of light or even instantaneously, that couldn't explain the odd behavior. The findings rule out certain "realist" interpretations of spooky quantum behavior. [Infographic: How Quantum Entanglement Works]

"What that tells us is that we have to look a little bit deeper," said study co-author Martin Ringbauer, a doctoral candidate in physics at the University of Queensland in Australia. "This kind of action-at-a-distance is not enough to explain quantum correlations" seen between entangled particles, Ringbauer said.
 

Mningasimisonda

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I admit that I have forever believed in the simulation theory that is now being talked about at the moment from Musk, Greene and others.

Quantum Entanglement to me is proof that you can send information across distances faster than light.

Since we are all information this will be our Warp Drive. Hurry up you dumb arse scientists, I wanna Millennium Falcon.
There's no known way to use entanglement to send information faster than the speed of light.

However, it is interesting that information seems to be at the centre of everything. Like why should the universe be undecided until observed or have a speed limit for information propagation. Wonder whether this is just the result our science and models being based on observing, or actually something fundamental in the workings of the universe (like a simulation or the universe being essentially a huge computer made up of it's entangled parts).
 

H2F

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There's no known way to use entanglement to send information faster than the speed of light.

However, it is interesting that information seems to be at the centre of everything. Like why should the universe be undecided until observed or have a speed limit for information propagation. Wonder whether this is just the result our science and models being based on observing, or actually something fundamental in the workings of the universe (like a simulation or the universe being essentially a huge computer made up of it's entangled parts).
I really believe in the below. It just is inarguable to me.

 

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