If we were in a simulation, would the speed of light be the processing speed of the universe as each area re-renders, and spooky action at a distance be two variables pointed to the same memory location, populated with a lazy-loaded value, with copy-on-write semantics?
edit: seems like it is lazy loaded, so revised my summary.
That's not a bad analogy, but you have to be very careful here because no classical analogy can be a perfect fit for entanglement. The wave function is deeply and fundamentally different than our classical reality, and there is no way to reproduce its behavior classically. Among the fundamental differences is the fact that classical information can be copied but quantum states cannot be cloned. This is IMHO the single biggest disconnect between the wave function and classical reality because the nature of our (classical) existence is fundamentally intertwingled with copying (classical) information. It is happening right now even as you read this. Information is being copied out of my brain onto the internets and into your brain. At the same time, all our cells are busily copying the information in our DNA, and so on and so on.
There are no propositions that "we are in simulation" would imply (unless someone fundamentally lacks imagination).
Being "in a simulation" doesn't imply that we're in simulation created by later humans, it doesn't give any indication how fine-grain the approximations are, etc. etc.
"We're in a simulation" fundamentally discard Occam's Razor in the fashion of the belief in God as controlling everything. And thus this belief has the same weight as belief in the Flying Spaghetti Monster [1].
If we were in a simulation, it feels overzealous to make the assumption that the computing model would be anything at all like what've developed. Best assumptions you can make is that it follows some kind of consistent logic (though there's caveats here, too).
Cellular automata have a built in speed limit, so it could be something like that. If one cell's state depends on only its immediate neighbors state, then logically no object can move faster than one cell diameter per frame. And if you had shared state between two non-adjacent cells in certain limited cases, that could create "faster than light" behavior.
You're probably interested in something more like the holographic universe hypothesis. Under that hypothesis, I believe "entangled particles" end up staying close to each other in the projected space. 3D space in that case would be an "emergent phenomenon" that isn't necessarily the "base data structure" of the simulation.
Speed of light would just be rule, like cellular automata rules, Planck distance is cell size and the rule is you may only move one cell per frame in any direction. Processing speed doesn't matter to us, it could take a million "years" to render a frame but we experience it in real-time.
As you say pointer to shared memory location is basically hidden variable theory, you could also move faster than the speed of light by simply updating your location to any value, I have done this in game hacking before you just need a WriteProcessMemory api, might get caught by anti-cheats.
Isn't it the non-local hidden variable model? The idea that if local hidden variables do do not explain Bell inequalities, make the hidden variables non-local.
I think this model kind of works and some scientists are working on it, but it is not the preferred interpretation.
It's not really immutable as you can change the parameters of an entangled pair. You just can't communicate any information by doing so, because you need a classical signal to make sure you don't read one of the particles the wrong way.
It did not prove that. It proved that at least one of three assumptions about the universe is violated: Statistical Independence, Locality or Determinism. The usual assumption is that Locality has to go, but that is not necessarily true. It is possible that Statistical Independence is not true for the experimental systems that have been studied.
I'll never understand entanglement. Every explanation makes me wonder why it can't be used to instantaneously send a message. I never fully understand the explanations why it can't be used to do so. I don't understand how you can be sure about the state of the other particle, what if someone already measured it and then did something to it?
Imagine you have a pouch with a red and a blue marble in it, then take out a marble without looking at it and hand the pouch to a friend. Later, if you look at your marble, you instantly have information about the other marble at a speed greater than the speed of light... but you couldn't use that fact to send a message.
The only difference in quantum physics is that there are actually two parallel universes: One in which you took out the red marble & one in which you took the blue one. You don't know what universe you're in until you look at the marble, but still it doesn't help you to transmit a message to your friend.
(This is assuming the "multiple universes" interpretation- In the other interpretations there is "spooky action at a distance", but this action happens in EXACTLY THE RIGHT WAY to prevent you from transmitting a message to your friend)
It can't be used to send a message because all you can do is measure your particle. Even if doing so changes the state of the other particle far away (which isn't really what's happening, but that doesn't matter), all the other person at the end can do is measure their particle.
Neither of you can choose what the state of either particle is. You have no control, so there's no way to transmit information.
What you can do is agree in advance that you will both take certain actions based on the measured state of the particles. There's no way to be sure the person at the other end actually does so though.
I find that this article [0] from Conway and Kochen is helpful. The authors do not really explain the paradoxes of quantum mechanics. Instead they reduce them to minimal fundamental axioms that have been tested and observed experimentally, even though they are arguably highly counter-intuitive (notably SPIN and TWIN). Based on those axioms, the authors show that you cannot send a message through entanglement. More precisely, they show that a particle has a free will, in the sense that the result of a measurement on it "is not a function of properties of that part of the universe that is earlier than this response".
Two balls are a box. Neither are spinning. The box gets “shaken up” and the balls hit each other. We know that one ball is spinning clockwise and the other is counter clockwise because angular momentum spin is conserved. The balls launch far away from each other. We know the spin is entangled in that one is clock wise the other is counter clockwise but we don’t know which is which until we measure. How do we use that to communicate?
> how you can be sure about the state of the other particle, what if someone already measured it and then did something to it?
Indeed, you are only sure about the state of the other particle in the instant just after they measured it. Whoever measures first instantly destroys the entanglement link, so if they chose to manipulate the particle after measurement, you will have no knowledge of these manipulations.
More generally, note that in quantum mechanics "reading" the state of a particle (i.e. performing a measurement) is drastically different than "writing" information by manipulating a particle. Most entanglement-related weirdness hinges on this fundamental asymmetry between "read" and "write" operations for quantum information.
Or even better than instantaneously, let's get messages sent to us from the future using a Ronald Lawrence Mallett time machine based on a ring laser's properties, such that at sufficient energies, the circulating laser might produce not just frame-dragging but also closed timelike curves (CTC), allowing time travel into the past. I cannot believe that Ronald Mallett's biggest challenge is getting funding for a feasibility test. Isn't it the greatest venture capital opportunity of all time?
Total layman, I’m sure I’ll get corrected if I’m wrong here:
Bell's Theorem is just a model showing how two sets of measurements of certain properties of entangled particles would differ in a “Quantum Physics” regime where there is spooky action at a distance changing the measured properties versus a “common sense” regime where both particles leave the entanglement site with those properties already set.
[0] is a fairly easy to understand graph of the correlation of the measurements at the two sites in both regimes, even if the math that generates those charts is beyond me.
Given that, just knowing what measurements you got only gives you an idea of what the other guy across the universe would see were he to measure your particle’s entangled partner - he has no more control over what those measurements actually are than you do, you just know that there’s a certain correlation between what you saw and what he saw. That’s why you can’t use Bell’s Theorem to communicate, neither one of you is actually controlling the measured property, there’s just a certain correlation between the measurements both of you got.
It seems to this layman that in order to communicate FTL using QM, you’d need a way to determine that the property being measured has already been “collapsed” (if that’s the right word) by spooky action at a distance, e.g if the other guy had already measured it. Bell’s Theorem gives us no way to determine if the other guy has actually made the measurements, it assumes that both you and he have both made those measurements.
Not a physicist, but my answer to you is that usually superliminal speeds is the price that physicists are willing to pay to explain what is observed in experiment. I get your objection to the rather convoluted argument that special relativity still applies to message transfer, but I accept it. John Preskill explains the information within entanglement with an analogy to a book. Normally with a book, you can read one page seperately from all the other pages. Further, if you unbound the book, and randomly distributed the pages to your friends, you could put your heads together and reconstruct the entire book. With a "quantum book", the information is encoded in the correlations between the observables, and you can only see the information when all the pages of the book are together and in the correct order. If you look at a single page of the quantum book, it's purely random gibberish, and you can't derive anything about the book by looking at a part of it.
Look up how entanglement is done experimentally. It will always involve a technology which can be used to classically transmit information at a distance.
What happens in entanglement is that the two entangled objects receive say an entangled photon, it is at this point where the two objects are entangled.
Entanglement is a dance of the statistical limits and position of a particle/object given a specific space/energy configuration (initial condition). From this we know the probability of where it can be, what states it can assume, and the limits of both—given the energy it takes to traverse space and assume those states at once.
They are entangled because once information of the states of one of the entangled objects is measured (mainly by analyzing the exiting photon), we can apodictically discern the state of the other.
> I'll never understand entanglement. Every explanation makes me wonder why it can't be used to instantaneously send a message.
Say you and Bob share a bunch of entangled particles. Bob wants to send you a message using those particles, so he takes one particle at a time and encodes his information. How would you know he did so? At the very least, Bob would still have to send you a classical signal to say he did something.
There are more subtle arguments why this doesn't work even at the particle level, but that at least should give you an idea why superluminal communication won't work.
Funny, I never understood how you could possibly send a message using entanglement. Try to explain how would you do it, and either you will understand why it can't be done... or earn a Nobel prize. Win-Win.
You can measure a particle's spin to be up or down. But you can't choose to measure it to be up. It's random and up to nature. This is exactly why it can't be used to send information.
Reminds me of the in-lore comms system in Mass Effect. I think the comms in the ship were two atoms that were entangled, allowing instant messages no matter how many lightyears away the ship was from Earth.
Let's say particles have a 'direction angle' that we can measure with a detector that only gives 'up' or 'down' relative to a direction angle measurement. We can change this direction angle measurement with a knob to set what the measured 'up' and 'down' answers are relative to the detector's direction angle. Further let's say particles can be quantum entangled so that when when two detectors are placed very far apart, many light years apart, say, and measure a quantum entangled pair of particles.
When the two detectors are set to the same, but arbitrary, angle, the detectors give the same answer. This is normal correlation. Quantum correlation says that as one dial moves away from the other reference point, the correlation falls off as a sine wave, not a linear decrease as would be expected by classic probability.
To see how bonkers this is, do the following experiment:
Set detector X to be at angle 0 and detector Y to give a 1% error rate. Call that 1% angle 'a'. So a sample experiment run might be:
In the above, 1 could be an 'up' and 0 could be a 'down' detection, say. For concreteness, let's just say A and B ran 100 detections and there was one difference between them (giving 1% error), represented by the third differing bit in the above.
Now let let's change both X and Y by the same angle so the relative error rate between them is still 1%, this might give something like:
X and Y still have one difference in the above, but now with the 8th position changed. So far this is nothing unexpected from classical probability.
Now, we know that from X(0) to Y(a) there's one change, from X(a) to Y(2a) there's one change. Classic probability says that there can be at most two flipped bits from X(0) to Y(2a). Quantum mechanics predicts three.
To convince yourself, try making a list of bits such that there's one difference between X(0) and Y(a), one difference between X(a) and Y(2a) but three differences from X(0) to Y(2a). It's impossible and this is the heart of Bell's theorem.
Bell's theorem is a classical probability statement, generalized from my above statement that if |X(0)-Y(a)|=1, |X(a)-Y(2a)|=1 then |X(0)-Y(2a)|<=2. Quantum entanglement violates Bell's inequality.
The 0 reference point has to be arbitrary (in the above it should really be X(ref_angle + a), Y(ref_angle + 2a), etc.) and you have to assume no faster than light communication (that is, independence) to get the contradiction. There are some further subtleties with the above argument but hopefully that's intuitive enough to follow why quantum entanglement is so counter intuitive.
It's easy to understand (I'm being a bit hyperbolic) if you can believe that space and time are emergent properties of matter and not required for the underlying physics.
I think I prefer Felder's explaination more than Quanta's. It's omitting some details (eg. the angles) but is better at explaining the difficulties of Bell's Inequality--why it seems like spooky action at a distance and why it cannot be used for communication.
Note that there is a very important property of entangled particles that is hardly ever mentioned in this kind of exposition, which IMHO casts a lot of light on what is really going on, and that is that entangled particles do not self-interfere the way non-entangled particles do. For more details see:
I don't think the paper justifies the statement as you put it, though perhaps you can point out what I'm missing. I don't think you can tell just from looking at the particle itself whether it has an entangled partner somewhere in the universe.
It is, however, possible to use the entangled partners to create systems with decidedly counter-intuitive properties that change the way the un-involved partner interacts. That's also the essence of Bell's Theorem.
It only works when you're controlling the experiment as a whole and thus not transmitting information faster than light... though you can set up the experiment in a way that makes the conventional transmission of information incredibly obscure. Bell's Theorem requires you to jump through a lot of hoops to exactly mimic that, which is why it took a long time to definitively rule out other interpretations of the experiments.
"This is the first of a set of papers that look at actual Einstein-Podolksy-Rosen (EPR) experiments from the point of view of a scientifically and statistically literate person who is not a specialist in quantum theory."
Couldn't that 'hidden variable' be just another dimension?
So while those particles might have been separated in space by a large distance, on that fifth dimension they haven't moved and are still sitting side by side.
If you "measure" the bits per character in the base 45 alphanumeric encoding used in QR code, you'd get 5.5 bits per character as 11 bits is used for two characters.
How is it possible to have information less than a bit, a partial bit? What is that ".5" part? Isn't a bit indivisible?
Only in the context of a character doublet is all information expressed. To know the "half bit" part, you cannot "look" at just one character, you have to look at the total. The information is shared between the two characters. Measuring the bits-per-character is only useful when considering the whole system. The "partial bits" is information smeared across the system. Changing the middle bit may change one, or both, characters.
Here's a 11 bit example, where the middle bit is changed and it changes both characters:
(11101001010 vs 11101101010, or '/L' vs '%8' encoded)
The same principle applies to information theory and cryptography. Security can be measured in "partial bits" because it's measured across something larger.
What is the prevailing theory to explain quantum entanglement? Must there be another dimension we cannot access or measure that is not subject to the laws of relativity? (I understand the laws of relativity break down at the quantum level but please ELI5)
Not necessarily. Bell's theorem assumes statistical independence, but that means that either spooky action at a distance is real, OR that experimenters do not have complete freedom to configure their instruments (aka superdeterminism).
> really permits instantaneous connections between far-apart location
The phrasing in this article is tricky, as it wasn't FTL communication that was proven; just that there are correlations between things that would require FTL communication, were they classical processes. This is an important point: https://xkcd.com/1591/
I'm not a Physicist. From what I understand, Bell's theorem only covers local hidden-variables and that this can still be explained using non-local theories like Bohm's. Can someone shed a bit of light on the non-local theories and if Bell's theorem addresses those as well?
MWI allows you to have entanglement without “spooky action at a distance”. However, it requires exponential blowup in representational complexity of the universe, which also feels aesthetically displeasing.
Does the article do justice to the hidden variables hypothesis?
In case of the hidden variables, the spin is a (3-dimensional?) value that is identified by the measurement result. In case of quantum theory we have have a probability distribution. How is that probability distribution different from a hidden variables, except that it's not a straight number but a function instead?
Speaking as a programmer, is the difference between hidden variables and quantum mechanics that the former postulate a real-valued property whereas the latter speak of something like a monad?
There's no spooky action at a distance. Let's imagine we have an entangled qubit system that consists of a superposition of the states (0,1) and (1,0), i.e. either part A is in state 0 and part B in state 1 or vice versa. When we perform a measurement on the first part of the system and obtain 1, it simply means that we have "branched" into the (1,0) state of the system. This branching is usually irreversible because of the decoherence caused by the measurement (which itself is just an ordinary quantum process). There is no information exchange or any type of exchange between the two parts of the system going on, we simply branch into a part of the probability space defined for the system. The question whether the other branches still exist then leads to either the "classical" interpretation of quantum mechanics or the "many worlds" interpretation. The latter seems to be favored today as we know that there's nothing special about the measurement process that causes the collapse of a wave function (it's a quantum process in itself), but in the end there's not really a way to test this so it's really more of a philosophical question.
Articles about "spooky action at a distance" should really mention this, as we have a much better understanding of the measurement process in quantum mechanics today than Einstein et. al. had when they wrote their paper.
[+] [-] ericb|4 years ago|reply
edit: seems like it is lazy loaded, so revised my summary.
[+] [-] lisper|4 years ago|reply
[+] [-] joe_the_user|4 years ago|reply
Being "in a simulation" doesn't imply that we're in simulation created by later humans, it doesn't give any indication how fine-grain the approximations are, etc. etc.
"We're in a simulation" fundamentally discard Occam's Razor in the fashion of the belief in God as controlling everything. And thus this belief has the same weight as belief in the Flying Spaghetti Monster [1].
[1] https://en.wikipedia.org/wiki/Flying_Spaghetti_Monster
[+] [-] dvt|4 years ago|reply
[+] [-] fallingknife|4 years ago|reply
[+] [-] jerf|4 years ago|reply
[+] [-] SigmundA|4 years ago|reply
As you say pointer to shared memory location is basically hidden variable theory, you could also move faster than the speed of light by simply updating your location to any value, I have done this in game hacking before you just need a WriteProcessMemory api, might get caught by anti-cheats.
[+] [-] stouset|4 years ago|reply
Edit: OP edited their original comment to be more accurate.
[+] [-] GuB-42|4 years ago|reply
I think this model kind of works and some scientists are working on it, but it is not the preferred interpretation.
[+] [-] someguyorother|4 years ago|reply
[+] [-] rendall|4 years ago|reply
If the Universe were {analogy} is {real thing} related to {analogous thing}?
[+] [-] fungiblecog|4 years ago|reply
See for example: https://www.frontiersin.org/articles/10.3389/fphy.2020.00139...
[+] [-] nsxwolf|4 years ago|reply
[+] [-] drcode|4 years ago|reply
The only difference in quantum physics is that there are actually two parallel universes: One in which you took out the red marble & one in which you took the blue one. You don't know what universe you're in until you look at the marble, but still it doesn't help you to transmit a message to your friend.
(This is assuming the "multiple universes" interpretation- In the other interpretations there is "spooky action at a distance", but this action happens in EXACTLY THE RIGHT WAY to prevent you from transmitting a message to your friend)
[+] [-] simonh|4 years ago|reply
Neither of you can choose what the state of either particle is. You have no control, so there's no way to transmit information.
What you can do is agree in advance that you will both take certain actions based on the measured state of the particles. There's no way to be sure the person at the other end actually does so though.
[+] [-] guyomes|4 years ago|reply
[0]: https://www.ams.org/notices/200902/rtx090200226p.pdf
[+] [-] snissn|4 years ago|reply
[+] [-] misiti3780|4 years ago|reply
https://en.wikipedia.org/wiki/Something_Deeply_Hidden
[+] [-] axelf4|4 years ago|reply
[+] [-] superposeur|4 years ago|reply
Indeed, you are only sure about the state of the other particle in the instant just after they measured it. Whoever measures first instantly destroys the entanglement link, so if they chose to manipulate the particle after measurement, you will have no knowledge of these manipulations.
More generally, note that in quantum mechanics "reading" the state of a particle (i.e. performing a measurement) is drastically different than "writing" information by manipulating a particle. Most entanglement-related weirdness hinges on this fundamental asymmetry between "read" and "write" operations for quantum information.
[+] [-] stevenjgarner|4 years ago|reply
[+] [-] crystalmeph|4 years ago|reply
Bell's Theorem is just a model showing how two sets of measurements of certain properties of entangled particles would differ in a “Quantum Physics” regime where there is spooky action at a distance changing the measured properties versus a “common sense” regime where both particles leave the entanglement site with those properties already set.
[0] is a fairly easy to understand graph of the correlation of the measurements at the two sites in both regimes, even if the math that generates those charts is beyond me.
Given that, just knowing what measurements you got only gives you an idea of what the other guy across the universe would see were he to measure your particle’s entangled partner - he has no more control over what those measurements actually are than you do, you just know that there’s a certain correlation between what you saw and what he saw. That’s why you can’t use Bell’s Theorem to communicate, neither one of you is actually controlling the measured property, there’s just a certain correlation between the measurements both of you got.
It seems to this layman that in order to communicate FTL using QM, you’d need a way to determine that the property being measured has already been “collapsed” (if that’s the right word) by spooky action at a distance, e.g if the other guy had already measured it. Bell’s Theorem gives us no way to determine if the other guy has actually made the measurements, it assumes that both you and he have both made those measurements.
[0]: https://en.wikipedia.org/wiki/Bell's_theorem#/media/File:Bel...
[+] [-] wwarner|4 years ago|reply
[+] [-] ethn|4 years ago|reply
What happens in entanglement is that the two entangled objects receive say an entangled photon, it is at this point where the two objects are entangled.
Entanglement is a dance of the statistical limits and position of a particle/object given a specific space/energy configuration (initial condition). From this we know the probability of where it can be, what states it can assume, and the limits of both—given the energy it takes to traverse space and assume those states at once.
They are entangled because once information of the states of one of the entangled objects is measured (mainly by analyzing the exiting photon), we can apodictically discern the state of the other.
[+] [-] PavleMiha|4 years ago|reply
[+] [-] naasking|4 years ago|reply
Say you and Bob share a bunch of entangled particles. Bob wants to send you a message using those particles, so he takes one particle at a time and encodes his information. How would you know he did so? At the very least, Bob would still have to send you a classical signal to say he did something.
There are more subtle arguments why this doesn't work even at the particle level, but that at least should give you an idea why superluminal communication won't work.
[+] [-] 725686|4 years ago|reply
[+] [-] blueplanet200|4 years ago|reply
[+] [-] unknown|4 years ago|reply
[deleted]
[+] [-] sergiotapia|4 years ago|reply
[+] [-] abetusk|4 years ago|reply
When the two detectors are set to the same, but arbitrary, angle, the detectors give the same answer. This is normal correlation. Quantum correlation says that as one dial moves away from the other reference point, the correlation falls off as a sine wave, not a linear decrease as would be expected by classic probability.
To see how bonkers this is, do the following experiment:
Set detector X to be at angle 0 and detector Y to give a 1% error rate. Call that 1% angle 'a'. So a sample experiment run might be:
In the above, 1 could be an 'up' and 0 could be a 'down' detection, say. For concreteness, let's just say A and B ran 100 detections and there was one difference between them (giving 1% error), represented by the third differing bit in the above.Now let let's change both X and Y by the same angle so the relative error rate between them is still 1%, this might give something like:
X and Y still have one difference in the above, but now with the 8th position changed. So far this is nothing unexpected from classical probability.Now, we know that from X(0) to Y(a) there's one change, from X(a) to Y(2a) there's one change. Classic probability says that there can be at most two flipped bits from X(0) to Y(2a). Quantum mechanics predicts three.
To convince yourself, try making a list of bits such that there's one difference between X(0) and Y(a), one difference between X(a) and Y(2a) but three differences from X(0) to Y(2a). It's impossible and this is the heart of Bell's theorem.
Bell's theorem is a classical probability statement, generalized from my above statement that if |X(0)-Y(a)|=1, |X(a)-Y(2a)|=1 then |X(0)-Y(2a)|<=2. Quantum entanglement violates Bell's inequality.
The 0 reference point has to be arbitrary (in the above it should really be X(ref_angle + a), Y(ref_angle + 2a), etc.) and you have to assume no faster than light communication (that is, independence) to get the contradiction. There are some further subtleties with the above argument but hopefully that's intuitive enough to follow why quantum entanglement is so counter intuitive.
EDIT: corrected X(a) bit string
[+] [-] codezero|4 years ago|reply
[+] [-] hintymad|4 years ago|reply
edit: I didn't mean it as an explanation of entanglement. Just thought it was a convenient joke.
[+] [-] Gunax|4 years ago|reply
http://www.felderbooks.com/papers/bell.html
I think I prefer Felder's explaination more than Quanta's. It's omitting some details (eg. the angles) but is better at explaining the difficulties of Bell's Inequality--why it seems like spooky action at a distance and why it cannot be used for communication.
[+] [-] lisper|4 years ago|reply
https://flownet.com/ron/QM.pdf
[+] [-] jfengel|4 years ago|reply
It is, however, possible to use the entangled partners to create systems with decidedly counter-intuitive properties that change the way the un-involved partner interacts. That's also the essence of Bell's Theorem.
It only works when you're controlling the experiment as a whole and thus not transmitting information faster than light... though you can set up the experiment in a way that makes the conventional transmission of information incredibly obscure. Bell's Theorem requires you to jump through a lot of hoops to exactly mimic that, which is why it took a long time to definitively rule out other interpretations of the experiments.
[+] [-] dQw4w9WgXcQ|4 years ago|reply
[+] [-] flubert|4 years ago|reply
https://arxiv.org/abs/quant-ph/9611037
...I wonder if anyone has ever followed up on Caroline Thompson's work after she passed away.
https://arxiv.org/abs/quant-ph/0210150
[+] [-] jussij|4 years ago|reply
So while those particles might have been separated in space by a large distance, on that fifth dimension they haven't moved and are still sitting side by side.
[+] [-] Zamicol|4 years ago|reply
How is it possible to have information less than a bit, a partial bit? What is that ".5" part? Isn't a bit indivisible?
Only in the context of a character doublet is all information expressed. To know the "half bit" part, you cannot "look" at just one character, you have to look at the total. The information is shared between the two characters. Measuring the bits-per-character is only useful when considering the whole system. The "partial bits" is information smeared across the system. Changing the middle bit may change one, or both, characters.
Here's a 11 bit example, where the middle bit is changed and it changes both characters: (11101001010 vs 11101101010, or '/L' vs '%8' encoded)
https://convert.zamicol.com/?in=11101001010&inAlpha=01&outAl...
https://convert.zamicol.com/?in=11101101010&inAlpha=01&outAl...
vs changing the last bit only changes the last character: (Using the preceding example, 11101101010 vs 11101101011, or '%8' vs '%9' encoded)
https://convert.zamicol.com/?in=11101101011&inAlpha=01&outAl...
The same principle applies to information theory and cryptography. Security can be measured in "partial bits" because it's measured across something larger.
[+] [-] willyg123|4 years ago|reply
[+] [-] naasking|4 years ago|reply
[+] [-] miguelmurca|4 years ago|reply
The phrasing in this article is tricky, as it wasn't FTL communication that was proven; just that there are correlations between things that would require FTL communication, were they classical processes. This is an important point: https://xkcd.com/1591/
[+] [-] kovac|4 years ago|reply
[+] [-] wyager|4 years ago|reply
[+] [-] choeger|4 years ago|reply
In case of the hidden variables, the spin is a (3-dimensional?) value that is identified by the measurement result. In case of quantum theory we have have a probability distribution. How is that probability distribution different from a hidden variables, except that it's not a straight number but a function instead?
Speaking as a programmer, is the difference between hidden variables and quantum mechanics that the former postulate a real-valued property whereas the latter speak of something like a monad?
[+] [-] steve76|4 years ago|reply
[deleted]
[+] [-] steve76|4 years ago|reply
[deleted]
[+] [-] qwerty456127|4 years ago|reply
[+] [-] ThePhysicist|4 years ago|reply
Articles about "spooky action at a distance" should really mention this, as we have a much better understanding of the measurement process in quantum mechanics today than Einstein et. al. had when they wrote their paper.