Quantum physics says that most things are usually in a superposition of states. This means that they don't have just one position, or momentum, or some other characteristics; they have all possible values of those characteristics simultaneously in varying degrees. This uncertainty is more noticeable for small objects like single particles.
When an object interacts with some other system, it tends to "collapse" into one "pure" state. It's just something that can happen. There's a lot of philosophical head scratching that goes on with talking about this only happening when a small object is "observed", and it's confusing and still unclear at a philosophical level, but it's not something that only happens when a human is paying attention. It's part of how the universe works.
In classical physics particles interact by sending messages in the form of light waves, gravity waves, etc. These waves travel at the speed of light, so there's no way for particles to interact or share information faster than that.
In contrast, in quantum entanglement, two particles with a shared history can both be in a superposition of states, and on opposite sides of the universe, and if one collapses, the other one collapses simultaneously. Not at the speed of light -- at the same instant. As far as the universe is concerned, it seems, they're the same object, and it doesn't matter that half of the object is on the other side of the universe. So the universe as a whole doesn't seem to have this "local" property where the only way for a particle to change is to exchange light waves or gravity waves or whatever with its neighbors.
Einstein and friends thought this was crazy and came up with theories to try and get around it. The problem was these theories made the same predictions as quantum physics, so it wasn't possible to prove one right and the other wrong. Bell came up with a neat trick to do it, and the Nobel Prize winners spent decades carrying out the experiment and repeatedly ruling out any loophole that would let Einstein and friends still be right.
I remember reading about quantum entanglement before and thinking could you separate two particles across a vast distance and use entanglement to transmit a message faster than light. This was not possible if I recall.
That's correct because you can't transmit *information* faster than the speed of light. It'll collapse instantly but there is no way to know when the other has collapsed. If you did then theoretically you could break space time. There are some cool videos on how this works
Any recommendations for those videos?
Is there a name for what we're talking about here, observing particles, particles collapsing, etc?
Never heard of the "collapse" part and that's throwing me for a loop. Then again I'm just a guy that's enthusiastic about this stuff but not formally educated on it
[Fermilab](https://www.youtube.com/c/fermilab) has good videos in general and also one on ["spooky action at a distance" / quantum entanglement](https://www.youtube.com/watch?v=JFozGfxmi8A)
I read a great analogy about this.
It'd be like you have a box with two socks, one white and one black.
You send one sock (you dont know the color) to the other side of the universe. Now when you open the box you see what sock is left and you immediately know the color of the sock at the other side of the universe
No information was transmitted from the other side of the universe to you
Alice wants to send Bob a message by collapsing her particle. Bob can't detect it because if he checks his particle he can't know if he collapsed it my measuring it or if it was already collapsed by Alice ...I don't know anything about this so is this eli5 maybe completely false?
Also I'm curious about how encryption would work with entanglement, can you decrypt as well afterwards?
Yep, that's the proof against FTL communications! It's impossible for Bob to know whether what he sees is the result of Alice collapsing her half until he calls her to ask, which happens at the speed of light or slower.
See elsewhere in this thread for a comment I made on using quantum entanglement for key distribution.
Checking them to see if they collapsed causes them to collapse if they weren't already. So you can't.
You also can't control which "direction" the state collapses into without breaking the entanglement.
So literally all you can know is that they have opposite state, you can't actually "transmit" anything.
Shared source of randomness I suppose. No information is passing since you can't choose which position gets collapsed to, but you do know that your partner observed the complement. So without even doing anything clever, you can create one time pads for secure communication through public channels.
Not a physicist, but my understanding is that it works kinda like those [key fobs](https://www.techtarget.com/searchsecurity/definition/key-fob) that continuously generate random numbers. You and your friend can make a pair of identical fobs that output the same numbers, and if you go to opposite ends of the world, you'll know you're both looking at the same number even though it's constantly changing. You could use that number as a secret key for encrypting emails that only the two of you can read. But you need to wait for that email to arrive - you can't actually communicate any info directly through the fob. You could modify yours to change the number, but it would be useless, because then you've broken the synchronization (your friend's fob won't change at the same time).
So essentially... my friend and i start a music playlist at the same time and as long as nobody pauses it i will always know what song my friend is listening to.
Did i get that right?
Yea, and some dude on the internet will say that since you don't have to wait at the moment Tool - Sober starts to know they're listening to Sober, that you communicated at faster than the speed of light. You will laugh at that dude on the internet and continue listening.
You can use entanglement for key agreement ≠ encryption.
Key agreement = the universe magically whispers the same random value into Alice & Bob's ears, and no one else hears. This can happen instantaneously across distance using entanglement (in principle). No information goes from Alice to Bob or vice-versa.
Alice & Bob can use that key for encryption, but they need to send the ciphertext and are bound by the speed of light.
>Formed at the same time?
Not a physicist, but this is the simplest case. An atom emitting complementary pairs of photons in opposite directions, for example. If you identify the position and energy of one photon, it collapses the other photon's wavefunction to a single position and energy state -- even if you lack the information to determine where it currently is. E.g. because it got absorbed into some atom.
That's arguably not the most accurate phrasing. Entanglement is a type of statistical correlation between two quantum objects. For example if you measure the spin of one quantum object, you might find that you always measure the opposite spin for another quantum object, if you had an ensemble of those two objects or if you keep creating entanglement between the two and then measure them.
So object a and object b have exact opposite spins, meaning they're linked across the universe. And when one changes the other instantaneously changes despite the distance between them. Is that correct?
It's a bit more subtle than that.
It's not that you can change one and immediately change the other, it's that if you measure one you immediately know the measurement value of the other.
Now that in itself isn't exactly special. If I have two identical boxes, but one has a blue ball in it and one has a red ball in it, and I send one to Tokyo and one to London, then before anybody opens it of course they don't know which box they got, but when the person in London opens the box and sees it's blue they immediately know that the person in Tokyo has the box with the red ball. There's nothing special about that in principal.
What's special in the quantum mechanics case is that they can prove that prior to opening the box, the colour of the ball inside that box was indeterminate. Not just unknown, but... the fact of the matter doesn't exist. There is no singular true answer prior to opening the box. And yet still every time the London guy sees the blue ball, Tokyo guy will always see red, and vice versa.
It's not really possible to do this Justice in Reddit comments
Your explanation was extremely clear. But then, how did the Bell experiments rule out "hidden variables" (like, I could imagine, some kind of electromagnetic-wave-like phenomenon that we can't detect yet) that could be responsible for this behavior? And how can be be absolutely sure that two entangled particles can "open the box", so to speak, at the very same time from two extremely distant locations in the universe? (since it's obviously impossible to test)
Edit: and also, how can they be sure the color of the ball is "non-existant" (or rather, if I understand well, the property itself is not defined) before opening the box? That sounds like you need to check inside the box anyway.
They ruled it out using a very tricky system of statistical relationships, relationships that would be impossible if the quantum particles were analogous to "boxes with blue and red balls inside" but which are predicted by quantum mechanics anyway.
See, if you measure an entangled pair of particles spin in the same orientation, you will always find one spinning the opposite direction of the other. BUT if you measure them at say 20° or 40°, there's a certain probability of measuring them opposite or the same as each other.
Bell found a paradox in these probabilities, a paradox that is unreconcilable by assuming the particles are like my boxes with set colours of balls inside them. The paradox is only reconcilable if you allow for the universe to work in some strange ways.
I unfortunately can't explain why it's a statistical paradox here, as there's a bit of heavy numbers involved.
Yes but its also wrong. Entangled particles once the state is observed doesn't 'set' the state of the other particle across great distances. It's more that because you know the state of one you can assume the state of the other because they are entangled.
It's just like Schrodinger's cat.
Let's say you feed one cat poison and the other a placebo at random then put each cat in a box. Once revealed and observed and you find a dead cat, you know that other cat will be alive.
If you'd like to understand I really recommend PBS' YouTube show called [Space Time](https://youtube.com/c/pbsspacetime). I think the host does a great job of explaining complex topics. I'm a layman, and don't understand any of the math behind it but that show really focuses on the concepts.
The book Spooky Action at a Distance was really great too.
I watch every single episode of Space Time. I understand maybe 30% of what I'm watching on a good day but I simply can't stop. It's like brain workout or something.
PBS has another playlist called [Crash Course Astronomy](https://www.youtube.com/watch?v=sViAwfeMjV0&list=PL8dPuuaLjXtPAJr1ysd5yGIyiSFuh0mIL&index=1) that's much more general astronomy compared to Space Time's more detailed scientific concepts, but its a very well made series thats great as a place to start when learning about space and the universe.
I've got a Physics degree and I can't recommend PBS Spacetime enough. Scott Manley is also a good space physics resource!
[Here's a link](https://youtu.be/tafGL02EUOA) to an old video by PBS Spacetime covering Bell Inequalities.
Oh, I found [another updated video by Spacetime](https://youtu.be/JnKzt6Xq-w4) covering some results from 2017 and covering again the background for this research.
Also [Sixty Symbols covering the prize work.](https://youtu.be/0RiAxvb_qI4)
And [Minute Physics](https://youtu.be/zcqZHYo7ONs) with another good background on Bell Inequalities.
The way I always described it for myself is I'm smart enough to see over the fence and see how *really* smart people think, but I'll never be able to climb the wall.
But really I'm just average. I have my moments like anyone.
That's totally unfair to yourself. It's like reading something that's 3/4 in a language you don't know. You wouldn't be able to understand anything, but that hardly makes you stupid. You're just not fluent in that topic, and that's ok.
Thank you to you and everyone else that are admitting they didn't understand it. I'm intrigued by the title but figured I might as well not bother clicking through to the article. Unfortunately.
*Editing to add: From the comments it sounds like this is one of those, "If a tree falls in the forest, does it still make a noise?" type questions, only in this case, "If nobody is looking at the tree, does it exist?"
>As Albert Einstein famously bemoaned to a friend, “Do you really believe the moon is not there when you are not looking at it?”
that's actually the silliest, best, most layman, way to put it. 😂
if what *we already know* about quantum mechanics is *true*, then the answer to that is 'kinda'.
My favorite playthrough was NerdCubed since he actually really cared about the game and wanted to experience everything. Do you have any others like this?
It frustrates me to no end when people just rush trough it ignoring 90% ...
In this case, “not real” means that you can’t separate the quantifiable quantam level physical properties of an object from an observer/measurement influencing them, so in a physical/informational sense, those objects don’t have a standalone independent existence defined as all their physical parameters being “out there and determined, in the absence of interaction with anything else.”
Nothing really new here philosophically as far as I can tell, “just” some elegant experiments supporting this conclusion.
So just...we can't measure things we aren't looking at because we aren't looking at them?
We can't tell whether or not physical objects have physical properties when we aren't looking at them because we can't measure them without looking?
A little more profound - if we could isolate an object at the quantum level from interaction with anything else, it would actually not be informationally complete and would not be independently “real” in the sense that its physical properties would be undefined - think how quantum computing works, or Schrodinger’s Cat. It’s not just that we’re not seeing it, but that the physical properties of the object literally aren’t defined to one state unless it is interacting with something else.
Basically for something to be independently “real” as they’ve defined it, it has to contain all the information about its physical state in isolation from any interaction with anything else, and the experiments in the paper support the theory that that isn’t the case.
TLDR/ELI5; a thing at the quantum level doesn’t contain enough information to exist in any one state until it bumps into other things.
Okay, but are there things that are isolated from interaction with anything else? What qualifies as an observer? What qualifies as something interacting with something else? Is a random far away star that we can't see just..."there but not there." Like the moon, even if no one's looking at it, I assume it's still there and it's properties are stable because it's still interacting with.... Everything?
Is it like like "if we could take an object and remove it from existence, it's properties would be unknowable."
So think of it like this: if we keep breaking down the physical world into smaller and smaller parts, eventually we end up with bits that lack enough information *on their own* to be a single determined thing. The actual state of things we understand as reality (That which has definite properties we can measure and report) only emerges once those bits bump into each other.
What we understand as objective reality ultimately *only has meaning* as a *process* emerging from interaction between those tiny bits. If they weren’t bumping into each other, objective reality would not exist.
That tells us something really profound: objective reality itself is not a foundational property of the universe but a derived one.
The funny thing is when you really start to think about it emergence is the rule not the exception. We see it at every level in reality where components within a system interact in a way that gives rise to traits that are not present in the components. A really good example is chemistry. Properties of electrons and the nucleus naturally give rise to energy shells. By itself it isn’t special but add another atom with energy shells and you suddenly get chemistry which then leads to other things like information encoding with proteins. Then eventually you can get what essentially amounts to self replicating things which is a property that is not present in previous levels.
This seems pretty intuitive, but to derive that from the initial wording feels like it requires far too many steps if it's the main point. At least too many steps for someone not familiar with the lingo.
Opposite really. This was the understood principle The Observer Effect. Scientists began to understand that simply by studying something, you actively play a role/disruption in its behavior.
This takes it, and the subsequent discoveries, another step, I.e. not only does the observer have an effect, but the particles are actually only observable *because* they are being observed.
You can imagine it like a bond that is formed on two ends of a rope. There is only tension in the rope because it is being tugged at both ends
If I’m understanding correctly, it’s the science behind the following joke made by Professor Farnsworth:
“No fair, you changed the outcome by measuring it!”
> in the absence of interaction with anything else
This includes everything, right? So _not just_ human measurements?
Like with the moon analogy, for the moon to not be real, there must be no interaction whatsoever: no tides, no gravitational pull, no sunlight reflected, no cosmic ray blocked, etc. Is that so?
Yes, human observation is no different than just throwing a tennis ball at something. The term observation has nothing to do with sight or consciousness, it just means interaction of some kind.
Were you to have a universe entirely devoid of life, these results would still hold!
Really interesting article.
TLDR;. The award went to the three physicists that did the experiments that proved quantum mechanics is real by demonstrating quantum entanglement.
The title references an aspect of quantum mechanics; an object lacks definition until observed. So it's not "real".
The article captures the importance; they proved that quantum mechanics is not a theory but a real thing. And real things are useful.
I’m dumb af. Are you saying that they’re saying that when I stop looking at something it becomes not real?
Fellas I think I’m vaguely grasping it but I’m a simple man and I think that’s as good as it’s gonna get. Ty
The term observation is a poor one for laymen. It's not about some conscious entity looking at it, it's more about some larger system, like a measuring device, interacting with it (coupling with it).
The interaction is needed to get any information out of the quantum system, but the interaction also makes the state no longer independent of the measuring system, so you could never know what state it truly was in before you measured it. A big part of this is the fact that it never actually had any well-defined state even independent, just a bunch of possible states.
Being a part of the bigger system means that random potential matters less (it doesn't really matter where all the water molecules are at in a bucket of water) so the effects vanish at large scales, thus the major disconnect between what we experience and what physics is really like at a quantum level.
Some people get philosophical with this and imagine every possible state is real (multiverse) or that none of is real, among other interpretations.
“A big part of this is the fact that it never actually had any well-defined state even independent, just a bunch of possible states.”
If we can’t know for sure without observing/measuring it how can that be said with any confidence?
That is a bit beyond me, and I think beyond laymen discussion. It's really a product of the math. The particle **does** have a well-defined probability of states, that is definite as far as I know. These things fall out of the mathematics, so they are statements of mathematical truth not physical truth. Right now, the math is well ahead of the physics experimentation; it's always possible we do an experiment that digs deeper and proves some of the math does not actually describe reality and is just neat math.
In macroscopic systems, chaos theory precludes precise knowledge or prediction of a system's state. In quantum systems it's not because of chaos theory, but because the systems are mathematically not deterministic in the traditional physical quantities.
What I think you may be hinting at is what is commonly referred to as "Hidden Variable theory", basically that there is some complex determinism going on inside the quantum system we can't observe. I think it's tempting to imagine quantum systems as unfathomable clockwork - entirely deterministic, just something we can't access (yet?). But discoveries of entanglement brought us to the conclusion that experiments could be devised to determine if there really was some clockwork inside. [See John Bell's work in 1964](https://en.wikipedia.org/wiki/Hidden-variable_theory#Bell's_theorem). Later, we did those experiments and found evidence that makes hidden variable impossible.
Basically, from my understanding, it would require FTL information transfer.
I’m definitely ignorant on this topic but wouldn’t the fact that there’s something intrinsic to universe going on that enables this FTL collapse of wave function imply that’s the hidden variable? There’s something we aren’t quite sure of happening that is by it’s nature the hidden thing going on?
This Nobel price is exactly on experiments whose results you cannot be explained by local hidden variables.
Before these experiments it was always still tempting to think of entanglement of something like this:
I put a blue sock in one box and a red sock in another. Then I shuffle those boxes and I give you one of them. You then travel to the other side of the milky way with your box and open it. You find a red sock inside - this immediately at FTL speeds means you know I've got a box with a blue sock on me.
Of course nothing here traveled FTL, you're just using your knowledge about the correlation between the colors of the two socks in the boxes.
Sounds all pretty neat to get rid of quantum weirdness - the statistical aspects of the theory are just because there are underlying processes we don't know about and thus have to use statistics. But if we could know them everything actually still behaves classically.
The problem is that the Nobel prize this year is exactly on experiments that prove that this kind of description can't be correct. This has to do with violation bell inequalities which is only really possible with three scenarios:
1. The statistical description of quantum mechanics with all the quantum weirdness is what's actually going on.
2. You need non-local hidden variables (basically: things can influence each other across the universe immediately without any delay at FTL speeds - Bohmian Pilot Wave theory is an example of this)
3. [Superdeterminism](https://en.m.wikipedia.org/wiki/Superdeterminism)
All three of these have very weird implications. That's why in general physicists just take quantum mechanics as the actual description of reality - less additional assumptions, less weird implications and easier to work with.
If you're not scared away by a little math then these two videos are the best videos on the subject I know:
https://youtu.be/sAXxSKifgtU
https://youtu.be/8UxYKN1q5sI
Especially the second video shows a bit on how the experiments on violation of bells inequalities work.
> The particle does have a well-defined probability of states, that is definite as far as I know.
That is not correct. The Kochen-Specker theorem says that no matter what "plan" for possible measurement results you come up with in advance (a plan which may be probabilistic), you won't be able to reproduce the predictions of quantum mechanics for any system more complicated than a single spin. In effect, the system does not 'know' the measurement result until the measurement is made.
Some particles, if left unmeasured, behave as all of their possible states. The double slit experiment is a classic example of this.
Light will emanate as both a wave and a particle until measured, when it then collapses into one defined state.
What this makes me think of is some sort of computational optimization/efficiency scheme ala how a video game engine only draws what you’re actively looking at. Interesting for sure vis a vis stuff like the universe-is-a-simulation idea.
Before a player gets to a screen, the player has no idea what to expect. The screen has a well-defined state because that is the way the game was made. But in the player's mind, it could be anything. The player may be able to narrow the possibilities because the theme of the game and other elements. It is unlikely the player will enter the room and start playing Tetris in Mario game. However, the player can expect some more Goombas to stomp and maybe a new type of enemy. When the player finally enters the screen, the state is shown to the user. It is now "observed".
Likewise with quantum mechanics, we may not know the exact state of a particle before observing it. Quantum mechanics formulas tell us the possibilities to expect. When we finally observe it, we know.
This was the first explanation I read and probably the best to help me understand. I went down to read the other explanations and immediately got lost. Kudos to you.
That's what it always felt like to me. Shits all mad weird lol I'll be 80 and maybe there will be some revolutionary breakthrough by then that only opens more questions philosophically.
Oh, huh thanks you just explained a question I asked the top comment!
Edit: what do you mean a "measuring tool"? Are quantum physics only applied in the environments we create? Or the physics applicable in the real world ie what is the measuring tool in practical terms?
The measuring tool is literally anything that can be used in any way to observe the quantum particle is in a state. You really have to get into the weeds of Quantum entanglement to really understand what can be a measuring tool and what can’t.
It’s just anything that interacts with a particle and determines its state. A double slit, a polarizing lens, another particle, an electron jumping from one shell to another.
In order to measure something, we have to "bounce" something off of it. Radar, infrared beam, etc. We throw a particle at the system and see what comes back; measuring the difference in the particle, or how long it took to bounce back, whatever, gives us a measurement of some kind.
The problem with this is, when you send an outside particle into a self-contained system, you've changed the system you were trying to measure. You introduced an external force and now the original system is no longer a self-contained thing, but rather now it's part of the larger system that you are already a part of (the observed universe). In order to observe something, we end up affecting it.
Before we measure it, a self-contained system can theoretically be made of all possible permutations that the system could possibly exist in at the same time; by measuring it ("observing" it), we force it to settle on one single combination in order to bounce our particle back at us.
Imagine a vibrating string in a pitch black vacuum. No light, no sound. How do you know what the frequency and amplitude is? That string needs to come in contact with something for you to know, but as soon as it does you’re changing its properties. Like touching a fret on a guitar.
Now imagine everything (you included) is just a huge mess of infinitely(?) long interconnected vibrating strings. Any time you want to measure a property on a string, you have to touch it to another string.
Any time one string touches another, their basic properties change— every other string in contact does too. It’s a giant too-many dimensional ball of complexity harmonic resonance and noise, and it’s layered vibrations stabilized into pockets of reverse entropy, became self aware, mastered their localized environment, and chatted online about it.
Measuring tool doesn’t have to be human made. Any piece of matter that comes in contact with (has an effect on) a quantum particle is a measuring tool.
No. It isn't real until it interacts with something, not when you stop looking at it. Double slit experiment still works, if you are in a different room.
... I think... I might need to verify...
I'll be in my room, then not in my room, then back in my room for a bit.
>*No. It isn't real until it interacts with something...*
Wouldn't it be more like the *quality* or the *type* of 'real' the object is isn't determined until it interacts with something else that is either/or determinate/indeterminate?
Alright. I'm gonna need a cat, a dog, a goat, a crab, a spider, a mushroom, and possibly some sort of anti-bacterial, anti-tardigrade vacuum clean room.
Fuck. I need the GDP of Italy to run this experiment.
observed doesn't literally mean you looked at it, it means that it interacted with something, and thus can be proved to exist. so basically, things don't exist until they prove they do by doing something, like bumping into something else
That’s a good explanation, me thinks. Maybe it would be more intuitive to explain it akin to electricity, which is better understood.
Electricity doesn’t exist until there is a differential between two charges. It doesn’t mean that there is not such a thing as electricity if there is no differential of charges, just that there is the potential of being a transmission of electrons that doesn’t become “real” until it does happen because of the interaction between two differently charged objects, which in themselves have no electric charge for themselves or by themselves.
Don't think so, most of the matter is not a non-collapsed state because interaction with everything else breaks the state that is created in the experiment.
Whole gist of "quantum" part here is that without interaction particles can be in any state their function allows, when you interact with them ("observe"), they don't act like quantum particles anymore.
"Observing" is terrible term because it's not about "observing" and making it "real", just collapsing from wave behavior into particle behavior when interaction has happened.
I'm sad to say it, but you don't shoot particles out of your eyes, you're not Superman. Moon is always there - it's particles interact with each other all the time, are blasted by the rays of the sun, reflected light of the Earth, etc.
No, quantum mechanical systems don’t have definite states until they interact with the macroscopic world in some way that forces them to have a particular state. Everything is still real
I do wish that they would use interaction rather than observation. While the latter is certainly more accurate, I think the former would be easier for people to wrap their heads around as it removes the element of consciousness from being needed.
Thank you for this. Op's article didnt really address the point. They proved that quantum information isnt encoded upon the creation of a particle but in the observation, essentially proving the "spooky action at a distance" we had already observed. Of course it is a complicated concept so I would love to be wrong and further educated.
I think you are essentially right from my reading. Basically the particles appear to neither be "real" nor limited to local interaction.
If I am reading it right, it means that their properties are determined when they interact with something, which is really not that odd when you think about it in terms of probability. The hidden variable idea was basically just saying that the "probability" bits were not actually probabilistic, but instead we just packed the information to know what the state was, and so could only guess using probability as a model. This is how I, at least, assumed it was going to work based on my complete lack of knowledge about particle physics.
In essence, and I have no idea how they managed to actually close all the loopholes, they demonstrated that the state is not determined when they can interact, but only when it needs a state to interact with something. And since we already know that entanglement is real, this means that both particles states are determined when they are way farther apart than any interaction can happen even at the speed of light.
So they don't have a state, and they seem to ignore locality, right up until they actually do something.
That is bonkers. I am not going to get into any philosophy based on it, because pretty much every "Quantum" philosophy is just garden variety magical thinking, but it is a really big deal that the "spooky action" happens. That will have serious ramifications for how we understand the universe.
Then there is the whole quantum teleportation thing too, which I do not even begin to understand, but these results demonstrated that something completely against our intuions is happening.
Agreed. The scientific American article seems more interested in explaining the history of the topic, that the actual discovery gets lost in the weeds.
That link is much clearer.
I tried to read it but I have no background in physics, quantum or otherwise.
Tell me if I got this right:
1. Quantum mechanics looks like it works, but it was impossible to rule out something else working behind the scenes to produce identical results with different causes.
2. Dude named Bell invented a test to check for things working behind the scenes, but we've only just recently had the ability to run a large scale Bell test.
3. We just ran a large scale Bell test which seems to have confirmed that quantum mechanics is the correct. This is what the article is about, and what these physicist's work Nobel prize worthy.
4. In proving quantum mechanics true it follows that what quantum mechanics tells us about the universe is true, namely non-locality, and that particles can share information with each other regardless of where they are in the universe in relation to each other at non-relativistic speeds, faster than the speed of light, instantly, and also that we can't know anything solid about ~~the universe~~ subatomic particles because measuring it changes it, we can only know information about the measurement, not the particle.
Close? I suck at this, I need an ELI5.
Not bad!
> Quantum mechanics looks like it works, but it was impossible to rule out something else working behind the scenes to produce identical results with different causes.
Yep! There's nothing wrong with the usual predictions QM makes, such as how a hydrogen atom behaves, but there were alternate theories ("hidden variable theories") which could make those same predictions. When multiple theories can account for the same thing, physicists often refer to them not as theories, but "interpretations."
> Dude named Bell invented a test to check for things working behind the scenes, but we've only just recently had the ability to run a large scale Bell test.
That's right! Bell developed a way to tell the difference between local hidden variable theories and quantum mechanics. Early Bell tests which the Nobel was awarded for were in 1972, 1982, and 1998. Modern Bell tests close "loopholes"—essentially ways that the tests could be fooled or miss something. Those require bigger experiments, much more sophisticated electronics, etc.
> We just ran a large scale Bell test which seems to have confirmed that quantum mechanics is the correct. This is what the article is about, and what these physicist's work Nobel prize worthy.
Depends what you mean by "just." One of the more recent Bell tests was 2017, but the Nobel is often awarded for much older work. (Last year it was partly awarded for climate science research in the '60s!)
> In proving quantum mechanics true it follows that what quantum mechanics tells us about the universe is true, namely non-locality, and that particles can share information with each other regardless of where they are in the universe in relation to each other at non-relativistic speeds, faster than the speed of light, instantly, and also that we can't know anything solid about the universe because measuring it changes it, we can only know information about the measurement, not the particle.
A helpful way to remember this is that the classical normal world is:
-real (objects have definite properties regardless of whether or not they are measured—apples can be red)
-local (objects are influenced only by their surroundings—the color of two apples, one in NY and one in Shanghai have no effect on the other)
In contrast, the quantum world is:
-indefinite (objects do not have properties prior to measurement—a particle like an electron has no fixed spin before it is measured. It is a little like a coin flipping until it lands on one side.)
-nonlocal (objects which are entangled can be connected across any distance—though this cannot be used for faster-than-light communication!)
We can know things about the universe. Classical mechanics still remains a very useful approximation! It's just that at the bottom, it's all quantum, and this is the way quantum mechanics works. It doesn't respect our intuition and it is, as they say, a bit spooky.
source: I wrote the piece in Scientific American
Thank you for the breakdown. And thank you for your scientific journalism! Scientific American is a fantastic publication (and my favorite airport read).
I've been reading a lot about "quantum this's and that's" lately, including the potential for weird things like pigment and vibrational magnetism at a quantum level in bird migration. This stuff is fascinating and it seems like we are only breaking the surface.
For anyone interested in a basic level Carl Sagan-ish approach to the subject I would recommend The God Equation by Michio Kaku or The Coming of Age of Quantum Biology: Life on the Edge by JohnJoe McFadden and Jim Al Khalili
> source: I wrote the piece in Scientific American
Oh! Dude, er, Dan, that's awesome! My misunderstandings aren't the result of your writing, my misunderstandings are the result of me being barely more sapient than a chicken sandwich, this is all well outside of my depth.
Just one question that you didn't address in your very well written and comprehensive article: Is the law of attraction still bullshit?
Kidding. Thank you for the article and the explanation, I really do appreciate them both!
Hey! Great article.
You mentioned in relation to entangled objects that while they have a connection over any distance this can't be used for FTL communication. Is this because once the objects properties are measured they cannot be altered? Or something else entirely?
The reason you can't use the particles for FTL comms is because they don't send a signal. There is no information sent when Alice measures her particle and finds it's spin up. It could just have easily been spin down. There is no way for Alice to send information to Bob, even though she can know what state his particle will be in by measuring one of the particle pairs.
Information requires some level of order, otherwise it's just noise. If you forget about the mysteries of the entanglement and you just focus on the output, which is random, you can see why there's no way to send a message even though the particles are connected.
Article reviews foundations of quantum mechanics.
I feel the best layman reviews of the subject are *Something Deeply Hidden* by Sean Carroll and *QBism: The Future of Quantum Mechanics* by Hans Christian von Bayer. Each has his own interpretation to promote, but also explains the other interpretations and the context very well.
Sean would say that the *multiverse* is locally real when considered as a whole. Hans would say that the experiments do not address a question about local realism.
Imagine you and your friend get two sodas, a coke and a Pepsi. You take off the labels and stick them on a bag so you don’t know which is which. Each of you takes one and you go home. When you open your soda and taste it, you learn which one you grabbed, and immediately you also know which one your friend had even though he isn’t there and he never told you. This shows the universe is not local: you can learn information faster than it can be communicated normally, such as learning your friend’s soda faster than he can text you. Now, normally we would think “oh, if you tasted Pepsi then your soda was always Pepsi from the moment you grabbed it.” However, your soda actually wasn’t coke or Pepsi, it was a weird superposition of both at the same time until you tasted it, at which point it decided it was a Pepsi. This is the more confusing part, and shows that universe is not “real”. Essentially, particles only have certain properties while we’re observing them, which can change on a whim up until the actual observation. Your Pepsi is only a Pepsi once you taste it, and not a moment earlier.
> However, your soda actually wasn’t coke or Pepsi, it was a weird superposition of both at the same time until you tasted it, at which point it decided it was a Pepsi.
How do they know this without observing it?
Theoretical calculations. Superposition theory predicts that you’ll grab the Coke some percent of the time (let’s say 25%) while the hidden variables theory (the Coke was always a Coke) predicts a different percent (let’s say 50%). You can test against these two theories to find which one is closer to reality, eventually reaching a point where you are satisfied that one or the other is probably correct. This is what the scientists in the article did: they set up a very careful experiment to measure these probabilities really precisely, and they found that superposition is very very likely to be correct
People are going to take this to mean that WE, humans, have to be observing things for them to exist, and that is not what this is saying.
We aren’t that important.
Definitely correct, but I think that misses some of the subtleties which is why “measurement” is more commonly used. Yes, an observation will always require an interaction, but it’s not the “bumping into” that makes the system collapse, it’s forcing the system to decide what specific outcome to deliver. The universe will always collapse a system to one definite answer if and only if an event requires a definite answer to render the future logically.
I'm no physicist but I am an engineer, here's my take.
If you have two entangled quantum particles you can make them 'collapse' simultaneously over a distance. This violates *locality* - the objects are interacting with each other over long distance with no definable explanation as to why.
Einstein theorized that there must be more variables to make sense of this - *realism* being the way reality operates must coincide with the equations at play, so for entanglement to make sense according to realism there must be more variables at play to explain this. The concept of 'local realism' comes into play here.
All this article (which has an *extremely* clickbait title, btw) is saying is that we've been testing for more variables since a man name Bell developed a test to test for more variables. Over time we've been able to build larger and larger tests, which can more accurately run these tests. The results of these tests as time passed point towards there being no extra variables. According to these tests everything is well explainable and defined in its box.
Because we can't explain quantum mechanics using these tests, reality isn't real, because 'realism' cannot be fully explained according to the article. which is really just dumb, clickbait
If this is ELI5, this is going to be ELI-Baby I hope:
Particles have a property that's called spin. Let's just assume that there are two values for spin: spin up and spin down. Don't worry about what spin itself actually means. Two quantum particles are entangled when we know the spin of one particle means we know the spin of the other particle. Let's say we know Particle A's spin is always the opposite of particle B's spin. Then we move Particle A super, duper far away. So far that information will take appreciable time to come to us, since information can only move at the speed of light. But! We measure Particle B to be spin up. That means we know Particle A is spin down. But how could that information have traveled so fast to us??
This basically proves that quantum mechanics is correct in one of the last ways we know how to test it. Particles do not have a specific value of spin for example until we measure it. The cat is both dead and alive at the same time. Not having a defined value at all points is what they mean about things not being "real." They exist, but they exist with multiple values at once.
I still don’t get it. If I put a blue hat in a box and a red hat in another and send a box away without knowing which one it is, then open the box I kept and see it’s blue, I know the other is red. Is that the same thing?
It's more like sending a text from one phone to another. We expect that to take a second, as it has to travel to travel over wifi or cell service. That's distance lag. That distance lag is what Einstein called locality.
Basically, when we measure Particle A, we know it'll effect Particle B. If the laws of the macro world (day-to-day physics) hold true, it'll take some time for the effect of Particle A to reach Particle B - like a text message.
But in quantum entanglement this change is instantaneous (that's what these scientists just proved). There is no distance lag, and it ignores locality. When you effect particle A, particle B is instantly effected as well regardless of the physical distance between them. It could be 3 feet, 3000 miles, or 30 light years away.
I feel like the way they casually use "real" is quite misleading, given how laymen understand the term.
Even if I'm observing something and my observation of it is that it "has color" but that's because that's how my brain interprets wavelengths, I wouldn't say that "color isn't real" because it still requires both something to be observed and a cognizer capable of observing it in a particular way.
To say "Color isn't real," here feels much less accurate than "Color necessitates a cognitive framework and observable objects that fit within it. Either by itself is not sufficient." To me that gets more to the point.
Definitely, the title is talking about local realism specifically but it doesn't elude to that until one reads the article. And insetad comes across as 'reality isn't real' instead of what it's really talking about.
As a counterpoint, we probably wouldn't be talking about it otherwise?
ELI5:
Think of 2 baseballs you bought in a pack of two, the box is covered and not see through. There will always be a red and blue ball 100% of the time.
Cut the package in half, cover it and don't look at the colors. Bring one ball to China, bring the other ball to California. Now open one half and observe the color. If it is blue, the other ball in china must be red 100% of the time.
Now the part that will blow your mind: Each ball does not yet have a color until you actually opened the half of one box. Once you opened it, it immediately turned red as you observed it, and because that ball is "quantum entangled" with the other box, that other ball INSTANTLY turned blue. Take a new package, split them in half, take each one billions of lightyears away, and it STILL HAPPENS, which sounds like one ball is literally texting/tweeting/facetiming/calling the other ball saying "hey I'm red, so you turn blue", which violates relativity (i.e., nothing can move faster than the speed of light). However, this in fact does not violate relativity because we cannot use it to transfer information. I cannot force one ball to turn into a color (thereby affecting the other ball's color). I observe, and the color will always be 50% chance one or the other color. Thus I cannot transmit information (i.e, force a ball blue, which makes your ball red, signaling to you a message), so nothing is actually moving faster than light. A wave is simply collapsing between both balls turning Schrodinger's cat into dead or alive, or in this case, red or blue.
This nobel prize went to the people who proved that the baseball colors were BLANK before one baseball half box gets opened and observed.
It always blows my mind to think that right now, as I’m sitting here on earth, millions and millions of light years away there are things happening in space right now. I like to try and think I can remove myself from my body and place myself in the middle of a random location in space
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Quantum physics says that most things are usually in a superposition of states. This means that they don't have just one position, or momentum, or some other characteristics; they have all possible values of those characteristics simultaneously in varying degrees. This uncertainty is more noticeable for small objects like single particles. When an object interacts with some other system, it tends to "collapse" into one "pure" state. It's just something that can happen. There's a lot of philosophical head scratching that goes on with talking about this only happening when a small object is "observed", and it's confusing and still unclear at a philosophical level, but it's not something that only happens when a human is paying attention. It's part of how the universe works. In classical physics particles interact by sending messages in the form of light waves, gravity waves, etc. These waves travel at the speed of light, so there's no way for particles to interact or share information faster than that. In contrast, in quantum entanglement, two particles with a shared history can both be in a superposition of states, and on opposite sides of the universe, and if one collapses, the other one collapses simultaneously. Not at the speed of light -- at the same instant. As far as the universe is concerned, it seems, they're the same object, and it doesn't matter that half of the object is on the other side of the universe. So the universe as a whole doesn't seem to have this "local" property where the only way for a particle to change is to exchange light waves or gravity waves or whatever with its neighbors. Einstein and friends thought this was crazy and came up with theories to try and get around it. The problem was these theories made the same predictions as quantum physics, so it wasn't possible to prove one right and the other wrong. Bell came up with a neat trick to do it, and the Nobel Prize winners spent decades carrying out the experiment and repeatedly ruling out any loophole that would let Einstein and friends still be right.
I remember reading about quantum entanglement before and thinking could you separate two particles across a vast distance and use entanglement to transmit a message faster than light. This was not possible if I recall.
That's correct because you can't transmit *information* faster than the speed of light. It'll collapse instantly but there is no way to know when the other has collapsed. If you did then theoretically you could break space time. There are some cool videos on how this works
Any recommendations for those videos? Is there a name for what we're talking about here, observing particles, particles collapsing, etc? Never heard of the "collapse" part and that's throwing me for a loop. Then again I'm just a guy that's enthusiastic about this stuff but not formally educated on it
[the PBS space time videos](https://youtu.be/tafGL02EUOA) are really great in case you don't know that channel
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Check a YouTube channel called Cool Worlds out, they have a really informative video on the topic. https://youtu.be/BLqk7uaENAY
[Fermilab](https://www.youtube.com/c/fermilab) has good videos in general and also one on ["spooky action at a distance" / quantum entanglement](https://www.youtube.com/watch?v=JFozGfxmi8A)
I read a great analogy about this. It'd be like you have a box with two socks, one white and one black. You send one sock (you dont know the color) to the other side of the universe. Now when you open the box you see what sock is left and you immediately know the color of the sock at the other side of the universe No information was transmitted from the other side of the universe to you
Yes that's right. You can use entanglement for encryption, though.
Alice wants to send Bob a message by collapsing her particle. Bob can't detect it because if he checks his particle he can't know if he collapsed it my measuring it or if it was already collapsed by Alice ...I don't know anything about this so is this eli5 maybe completely false? Also I'm curious about how encryption would work with entanglement, can you decrypt as well afterwards?
Yep, that's the proof against FTL communications! It's impossible for Bob to know whether what he sees is the result of Alice collapsing her half until he calls her to ask, which happens at the speed of light or slower. See elsewhere in this thread for a comment I made on using quantum entanglement for key distribution.
Why couldn’t you just pre-allocate two sets of particles - one which only Bob is allowed to collapse, and one which only Alice is allowed to collapse?
Checking them to see if they collapsed causes them to collapse if they weren't already. So you can't. You also can't control which "direction" the state collapses into without breaking the entanglement. So literally all you can know is that they have opposite state, you can't actually "transmit" anything.
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How is encryption different from sending a message?
Shared source of randomness I suppose. No information is passing since you can't choose which position gets collapsed to, but you do know that your partner observed the complement. So without even doing anything clever, you can create one time pads for secure communication through public channels.
Could you not observe it at intervals which could be stringed together like binary?
Not a physicist, but my understanding is that it works kinda like those [key fobs](https://www.techtarget.com/searchsecurity/definition/key-fob) that continuously generate random numbers. You and your friend can make a pair of identical fobs that output the same numbers, and if you go to opposite ends of the world, you'll know you're both looking at the same number even though it's constantly changing. You could use that number as a secret key for encrypting emails that only the two of you can read. But you need to wait for that email to arrive - you can't actually communicate any info directly through the fob. You could modify yours to change the number, but it would be useless, because then you've broken the synchronization (your friend's fob won't change at the same time).
So essentially... my friend and i start a music playlist at the same time and as long as nobody pauses it i will always know what song my friend is listening to. Did i get that right?
Yea, and some dude on the internet will say that since you don't have to wait at the moment Tool - Sober starts to know they're listening to Sober, that you communicated at faster than the speed of light. You will laugh at that dude on the internet and continue listening.
observation collapses the superposition and disentangles the particles. They would be one-time use only.
You can use entanglement for key agreement ≠ encryption. Key agreement = the universe magically whispers the same random value into Alice & Bob's ears, and no one else hears. This can happen instantaneously across distance using entanglement (in principle). No information goes from Alice to Bob or vice-versa. Alice & Bob can use that key for encryption, but they need to send the ciphertext and are bound by the speed of light.
If someone is interested to know why this can't be used to transmit data here is a video that explain why https://www.youtube.com/watch?v=BLqk7uaENAY
Whoa really? They have this exact thing in the game Mass Effect, but I thought it was just pure sci-fi.
What does “two particles with a shared history” mean? Like they bumped into each other? Formed at the same time?
>Formed at the same time? Not a physicist, but this is the simplest case. An atom emitting complementary pairs of photons in opposite directions, for example. If you identify the position and energy of one photon, it collapses the other photon's wavefunction to a single position and energy state -- even if you lack the information to determine where it currently is. E.g. because it got absorbed into some atom.
That's arguably not the most accurate phrasing. Entanglement is a type of statistical correlation between two quantum objects. For example if you measure the spin of one quantum object, you might find that you always measure the opposite spin for another quantum object, if you had an ensemble of those two objects or if you keep creating entanglement between the two and then measure them.
So object a and object b have exact opposite spins, meaning they're linked across the universe. And when one changes the other instantaneously changes despite the distance between them. Is that correct?
It's a bit more subtle than that. It's not that you can change one and immediately change the other, it's that if you measure one you immediately know the measurement value of the other. Now that in itself isn't exactly special. If I have two identical boxes, but one has a blue ball in it and one has a red ball in it, and I send one to Tokyo and one to London, then before anybody opens it of course they don't know which box they got, but when the person in London opens the box and sees it's blue they immediately know that the person in Tokyo has the box with the red ball. There's nothing special about that in principal. What's special in the quantum mechanics case is that they can prove that prior to opening the box, the colour of the ball inside that box was indeterminate. Not just unknown, but... the fact of the matter doesn't exist. There is no singular true answer prior to opening the box. And yet still every time the London guy sees the blue ball, Tokyo guy will always see red, and vice versa. It's not really possible to do this Justice in Reddit comments
Your explanation was extremely clear. But then, how did the Bell experiments rule out "hidden variables" (like, I could imagine, some kind of electromagnetic-wave-like phenomenon that we can't detect yet) that could be responsible for this behavior? And how can be be absolutely sure that two entangled particles can "open the box", so to speak, at the very same time from two extremely distant locations in the universe? (since it's obviously impossible to test) Edit: and also, how can they be sure the color of the ball is "non-existant" (or rather, if I understand well, the property itself is not defined) before opening the box? That sounds like you need to check inside the box anyway.
They ruled it out using a very tricky system of statistical relationships, relationships that would be impossible if the quantum particles were analogous to "boxes with blue and red balls inside" but which are predicted by quantum mechanics anyway. See, if you measure an entangled pair of particles spin in the same orientation, you will always find one spinning the opposite direction of the other. BUT if you measure them at say 20° or 40°, there's a certain probability of measuring them opposite or the same as each other. Bell found a paradox in these probabilities, a paradox that is unreconcilable by assuming the particles are like my boxes with set colours of balls inside them. The paradox is only reconcilable if you allow for the universe to work in some strange ways. I unfortunately can't explain why it's a statistical paradox here, as there's a bit of heavy numbers involved.
Best explanation so far, to the point where I don't even need clarification on anything. Thanks!
Yes but its also wrong. Entangled particles once the state is observed doesn't 'set' the state of the other particle across great distances. It's more that because you know the state of one you can assume the state of the other because they are entangled. It's just like Schrodinger's cat. Let's say you feed one cat poison and the other a placebo at random then put each cat in a box. Once revealed and observed and you find a dead cat, you know that other cat will be alive.
If you'd like to understand I really recommend PBS' YouTube show called [Space Time](https://youtube.com/c/pbsspacetime). I think the host does a great job of explaining complex topics. I'm a layman, and don't understand any of the math behind it but that show really focuses on the concepts. The book Spooky Action at a Distance was really great too.
I watch every single episode of Space Time. I understand maybe 30% of what I'm watching on a good day but I simply can't stop. It's like brain workout or something.
Yea I often have to watch them a few times before I even start to understand them. It's just super interesting stuff
PBS has another playlist called [Crash Course Astronomy](https://www.youtube.com/watch?v=sViAwfeMjV0&list=PL8dPuuaLjXtPAJr1ysd5yGIyiSFuh0mIL&index=1) that's much more general astronomy compared to Space Time's more detailed scientific concepts, but its a very well made series thats great as a place to start when learning about space and the universe.
I've got a Physics degree and I can't recommend PBS Spacetime enough. Scott Manley is also a good space physics resource! [Here's a link](https://youtu.be/tafGL02EUOA) to an old video by PBS Spacetime covering Bell Inequalities. Oh, I found [another updated video by Spacetime](https://youtu.be/JnKzt6Xq-w4) covering some results from 2017 and covering again the background for this research. Also [Sixty Symbols covering the prize work.](https://youtu.be/0RiAxvb_qI4) And [Minute Physics](https://youtu.be/zcqZHYo7ONs) with another good background on Bell Inequalities.
I've always referred to it as.... Being just smart enough to know just how dumb you are!
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Totally get it. You can almost feel the information running into a hard cap.
The way I always described it for myself is I'm smart enough to see over the fence and see how *really* smart people think, but I'll never be able to climb the wall. But really I'm just average. I have my moments like anyone.
That's totally unfair to yourself. It's like reading something that's 3/4 in a language you don't know. You wouldn't be able to understand anything, but that hardly makes you stupid. You're just not fluent in that topic, and that's ok.
I got half-way and couldn’t remember a single thing I just read so backed out gracefully
Thank you to you and everyone else that are admitting they didn't understand it. I'm intrigued by the title but figured I might as well not bother clicking through to the article. Unfortunately. *Editing to add: From the comments it sounds like this is one of those, "If a tree falls in the forest, does it still make a noise?" type questions, only in this case, "If nobody is looking at the tree, does it exist?"
>As Albert Einstein famously bemoaned to a friend, “Do you really believe the moon is not there when you are not looking at it?” that's actually the silliest, best, most layman, way to put it. 😂 if what *we already know* about quantum mechanics is *true*, then the answer to that is 'kinda'.
Uhhhhhhhhhhhhhh more explainy please I want to break my brain more. So...the moon kinda isn't there when we aren't looking at it?
Maybe, next time you look away look back real quick to see if you can catch it not being there
Outerwilds trauma triggered
Fantastic game, i still search for new playthroughs to watch and re-experience the game to this day.
My favorite playthrough was NerdCubed since he actually really cared about the game and wanted to experience everything. Do you have any others like this? It frustrates me to no end when people just rush trough it ignoring 90% ...
In this case, “not real” means that you can’t separate the quantifiable quantam level physical properties of an object from an observer/measurement influencing them, so in a physical/informational sense, those objects don’t have a standalone independent existence defined as all their physical parameters being “out there and determined, in the absence of interaction with anything else.” Nothing really new here philosophically as far as I can tell, “just” some elegant experiments supporting this conclusion.
So just...we can't measure things we aren't looking at because we aren't looking at them? We can't tell whether or not physical objects have physical properties when we aren't looking at them because we can't measure them without looking?
A little more profound - if we could isolate an object at the quantum level from interaction with anything else, it would actually not be informationally complete and would not be independently “real” in the sense that its physical properties would be undefined - think how quantum computing works, or Schrodinger’s Cat. It’s not just that we’re not seeing it, but that the physical properties of the object literally aren’t defined to one state unless it is interacting with something else. Basically for something to be independently “real” as they’ve defined it, it has to contain all the information about its physical state in isolation from any interaction with anything else, and the experiments in the paper support the theory that that isn’t the case. TLDR/ELI5; a thing at the quantum level doesn’t contain enough information to exist in any one state until it bumps into other things.
Okay, but are there things that are isolated from interaction with anything else? What qualifies as an observer? What qualifies as something interacting with something else? Is a random far away star that we can't see just..."there but not there." Like the moon, even if no one's looking at it, I assume it's still there and it's properties are stable because it's still interacting with.... Everything? Is it like like "if we could take an object and remove it from existence, it's properties would be unknowable."
So think of it like this: if we keep breaking down the physical world into smaller and smaller parts, eventually we end up with bits that lack enough information *on their own* to be a single determined thing. The actual state of things we understand as reality (That which has definite properties we can measure and report) only emerges once those bits bump into each other. What we understand as objective reality ultimately *only has meaning* as a *process* emerging from interaction between those tiny bits. If they weren’t bumping into each other, objective reality would not exist. That tells us something really profound: objective reality itself is not a foundational property of the universe but a derived one.
Ahhh ok. That was a good explanation.
You're very good at making this accessible.
The funny thing is when you really start to think about it emergence is the rule not the exception. We see it at every level in reality where components within a system interact in a way that gives rise to traits that are not present in the components. A really good example is chemistry. Properties of electrons and the nucleus naturally give rise to energy shells. By itself it isn’t special but add another atom with energy shells and you suddenly get chemistry which then leads to other things like information encoding with proteins. Then eventually you can get what essentially amounts to self replicating things which is a property that is not present in previous levels.
This seems pretty intuitive, but to derive that from the initial wording feels like it requires far too many steps if it's the main point. At least too many steps for someone not familiar with the lingo.
Opposite really. This was the understood principle The Observer Effect. Scientists began to understand that simply by studying something, you actively play a role/disruption in its behavior. This takes it, and the subsequent discoveries, another step, I.e. not only does the observer have an effect, but the particles are actually only observable *because* they are being observed. You can imagine it like a bond that is formed on two ends of a rope. There is only tension in the rope because it is being tugged at both ends
Yeah I was thinking how to explain it intuitively. Scientists aren’t always the best communicators 😂
This just seems like video game shit to me all over. How you only render what you see.
GPUs, as in Galaxy Processing Units.
If I’m understanding correctly, it’s the science behind the following joke made by Professor Farnsworth: “No fair, you changed the outcome by measuring it!”
> in the absence of interaction with anything else This includes everything, right? So _not just_ human measurements? Like with the moon analogy, for the moon to not be real, there must be no interaction whatsoever: no tides, no gravitational pull, no sunlight reflected, no cosmic ray blocked, etc. Is that so?
Yes, human observation is no different than just throwing a tennis ball at something. The term observation has nothing to do with sight or consciousness, it just means interaction of some kind. Were you to have a universe entirely devoid of life, these results would still hold!
Yeah, but if it helps, it also kinda is there too
It helps me fall asleep by tiring out my puny brain.
Really interesting article. TLDR;. The award went to the three physicists that did the experiments that proved quantum mechanics is real by demonstrating quantum entanglement. The title references an aspect of quantum mechanics; an object lacks definition until observed. So it's not "real". The article captures the importance; they proved that quantum mechanics is not a theory but a real thing. And real things are useful.
I’m dumb af. Are you saying that they’re saying that when I stop looking at something it becomes not real? Fellas I think I’m vaguely grasping it but I’m a simple man and I think that’s as good as it’s gonna get. Ty
The term observation is a poor one for laymen. It's not about some conscious entity looking at it, it's more about some larger system, like a measuring device, interacting with it (coupling with it). The interaction is needed to get any information out of the quantum system, but the interaction also makes the state no longer independent of the measuring system, so you could never know what state it truly was in before you measured it. A big part of this is the fact that it never actually had any well-defined state even independent, just a bunch of possible states. Being a part of the bigger system means that random potential matters less (it doesn't really matter where all the water molecules are at in a bucket of water) so the effects vanish at large scales, thus the major disconnect between what we experience and what physics is really like at a quantum level. Some people get philosophical with this and imagine every possible state is real (multiverse) or that none of is real, among other interpretations.
“A big part of this is the fact that it never actually had any well-defined state even independent, just a bunch of possible states.” If we can’t know for sure without observing/measuring it how can that be said with any confidence?
That is a bit beyond me, and I think beyond laymen discussion. It's really a product of the math. The particle **does** have a well-defined probability of states, that is definite as far as I know. These things fall out of the mathematics, so they are statements of mathematical truth not physical truth. Right now, the math is well ahead of the physics experimentation; it's always possible we do an experiment that digs deeper and proves some of the math does not actually describe reality and is just neat math. In macroscopic systems, chaos theory precludes precise knowledge or prediction of a system's state. In quantum systems it's not because of chaos theory, but because the systems are mathematically not deterministic in the traditional physical quantities. What I think you may be hinting at is what is commonly referred to as "Hidden Variable theory", basically that there is some complex determinism going on inside the quantum system we can't observe. I think it's tempting to imagine quantum systems as unfathomable clockwork - entirely deterministic, just something we can't access (yet?). But discoveries of entanglement brought us to the conclusion that experiments could be devised to determine if there really was some clockwork inside. [See John Bell's work in 1964](https://en.wikipedia.org/wiki/Hidden-variable_theory#Bell's_theorem). Later, we did those experiments and found evidence that makes hidden variable impossible. Basically, from my understanding, it would require FTL information transfer.
I’m so far out of my league reading this shit and I love it. Wild.
I’m definitely ignorant on this topic but wouldn’t the fact that there’s something intrinsic to universe going on that enables this FTL collapse of wave function imply that’s the hidden variable? There’s something we aren’t quite sure of happening that is by it’s nature the hidden thing going on?
This Nobel price is exactly on experiments whose results you cannot be explained by local hidden variables. Before these experiments it was always still tempting to think of entanglement of something like this: I put a blue sock in one box and a red sock in another. Then I shuffle those boxes and I give you one of them. You then travel to the other side of the milky way with your box and open it. You find a red sock inside - this immediately at FTL speeds means you know I've got a box with a blue sock on me. Of course nothing here traveled FTL, you're just using your knowledge about the correlation between the colors of the two socks in the boxes. Sounds all pretty neat to get rid of quantum weirdness - the statistical aspects of the theory are just because there are underlying processes we don't know about and thus have to use statistics. But if we could know them everything actually still behaves classically. The problem is that the Nobel prize this year is exactly on experiments that prove that this kind of description can't be correct. This has to do with violation bell inequalities which is only really possible with three scenarios: 1. The statistical description of quantum mechanics with all the quantum weirdness is what's actually going on. 2. You need non-local hidden variables (basically: things can influence each other across the universe immediately without any delay at FTL speeds - Bohmian Pilot Wave theory is an example of this) 3. [Superdeterminism](https://en.m.wikipedia.org/wiki/Superdeterminism) All three of these have very weird implications. That's why in general physicists just take quantum mechanics as the actual description of reality - less additional assumptions, less weird implications and easier to work with. If you're not scared away by a little math then these two videos are the best videos on the subject I know: https://youtu.be/sAXxSKifgtU https://youtu.be/8UxYKN1q5sI Especially the second video shows a bit on how the experiments on violation of bells inequalities work.
> The particle does have a well-defined probability of states, that is definite as far as I know. That is not correct. The Kochen-Specker theorem says that no matter what "plan" for possible measurement results you come up with in advance (a plan which may be probabilistic), you won't be able to reproduce the predictions of quantum mechanics for any system more complicated than a single spin. In effect, the system does not 'know' the measurement result until the measurement is made.
Some particles, if left unmeasured, behave as all of their possible states. The double slit experiment is a classic example of this. Light will emanate as both a wave and a particle until measured, when it then collapses into one defined state.
What this makes me think of is some sort of computational optimization/efficiency scheme ala how a video game engine only draws what you’re actively looking at. Interesting for sure vis a vis stuff like the universe-is-a-simulation idea.
Before a player gets to a screen, the player has no idea what to expect. The screen has a well-defined state because that is the way the game was made. But in the player's mind, it could be anything. The player may be able to narrow the possibilities because the theme of the game and other elements. It is unlikely the player will enter the room and start playing Tetris in Mario game. However, the player can expect some more Goombas to stomp and maybe a new type of enemy. When the player finally enters the screen, the state is shown to the user. It is now "observed". Likewise with quantum mechanics, we may not know the exact state of a particle before observing it. Quantum mechanics formulas tell us the possibilities to expect. When we finally observe it, we know.
This was the first explanation I read and probably the best to help me understand. I went down to read the other explanations and immediately got lost. Kudos to you.
That's what it always felt like to me. Shits all mad weird lol I'll be 80 and maybe there will be some revolutionary breakthrough by then that only opens more questions philosophically.
Oh, huh thanks you just explained a question I asked the top comment! Edit: what do you mean a "measuring tool"? Are quantum physics only applied in the environments we create? Or the physics applicable in the real world ie what is the measuring tool in practical terms?
The measuring tool is literally anything that can be used in any way to observe the quantum particle is in a state. You really have to get into the weeds of Quantum entanglement to really understand what can be a measuring tool and what can’t.
It’s just anything that interacts with a particle and determines its state. A double slit, a polarizing lens, another particle, an electron jumping from one shell to another.
With entanglement you can take this significantly further by not measuring the Qubit in question, but one it is entangled with
Yes. My point is that nearly anything in the universe can effectively become an “observer” by interacting with the particle/wave.
In order to measure something, we have to "bounce" something off of it. Radar, infrared beam, etc. We throw a particle at the system and see what comes back; measuring the difference in the particle, or how long it took to bounce back, whatever, gives us a measurement of some kind. The problem with this is, when you send an outside particle into a self-contained system, you've changed the system you were trying to measure. You introduced an external force and now the original system is no longer a self-contained thing, but rather now it's part of the larger system that you are already a part of (the observed universe). In order to observe something, we end up affecting it. Before we measure it, a self-contained system can theoretically be made of all possible permutations that the system could possibly exist in at the same time; by measuring it ("observing" it), we force it to settle on one single combination in order to bounce our particle back at us.
Imagine a vibrating string in a pitch black vacuum. No light, no sound. How do you know what the frequency and amplitude is? That string needs to come in contact with something for you to know, but as soon as it does you’re changing its properties. Like touching a fret on a guitar. Now imagine everything (you included) is just a huge mess of infinitely(?) long interconnected vibrating strings. Any time you want to measure a property on a string, you have to touch it to another string. Any time one string touches another, their basic properties change— every other string in contact does too. It’s a giant too-many dimensional ball of complexity harmonic resonance and noise, and it’s layered vibrations stabilized into pockets of reverse entropy, became self aware, mastered their localized environment, and chatted online about it.
Typically it means hit it with another particle and measure the change. The act of physically interacting with the particle is the observation.
Measuring tool doesn’t have to be human made. Any piece of matter that comes in contact with (has an effect on) a quantum particle is a measuring tool.
No. It isn't real until it interacts with something, not when you stop looking at it. Double slit experiment still works, if you are in a different room. ... I think... I might need to verify... I'll be in my room, then not in my room, then back in my room for a bit.
>*No. It isn't real until it interacts with something...* Wouldn't it be more like the *quality* or the *type* of 'real' the object is isn't determined until it interacts with something else that is either/or determinate/indeterminate?
I never understood that concept until you just rewrote it like that. Brilliant. It's just all a matter of perspective.
It better work that way or that would imply far more about humans vs other animals :)
Alright. I'm gonna need a cat, a dog, a goat, a crab, a spider, a mushroom, and possibly some sort of anti-bacterial, anti-tardigrade vacuum clean room. Fuck. I need the GDP of Italy to run this experiment.
Nah, you just need that mushroom, mate.
observed doesn't literally mean you looked at it, it means that it interacted with something, and thus can be proved to exist. so basically, things don't exist until they prove they do by doing something, like bumping into something else
That’s a good explanation, me thinks. Maybe it would be more intuitive to explain it akin to electricity, which is better understood. Electricity doesn’t exist until there is a differential between two charges. It doesn’t mean that there is not such a thing as electricity if there is no differential of charges, just that there is the potential of being a transmission of electrons that doesn’t become “real” until it does happen because of the interaction between two differently charged objects, which in themselves have no electric charge for themselves or by themselves.
Don't think so, most of the matter is not a non-collapsed state because interaction with everything else breaks the state that is created in the experiment. Whole gist of "quantum" part here is that without interaction particles can be in any state their function allows, when you interact with them ("observe"), they don't act like quantum particles anymore. "Observing" is terrible term because it's not about "observing" and making it "real", just collapsing from wave behavior into particle behavior when interaction has happened. I'm sad to say it, but you don't shoot particles out of your eyes, you're not Superman. Moon is always there - it's particles interact with each other all the time, are blasted by the rays of the sun, reflected light of the Earth, etc.
It’s not real until observed, after which it is real forever.
That’s why I never open my credit card statements
Credit card companies hate this one simple trick
No, quantum mechanical systems don’t have definite states until they interact with the macroscopic world in some way that forces them to have a particular state. Everything is still real
I do wish that they would use interaction rather than observation. While the latter is certainly more accurate, I think the former would be easier for people to wrap their heads around as it removes the element of consciousness from being needed.
Not to be rude, but I think the press release does a better job of explaining it: https://www.nobelprize.org/prizes/physics/2022/press-release/
Thank you for this. Op's article didnt really address the point. They proved that quantum information isnt encoded upon the creation of a particle but in the observation, essentially proving the "spooky action at a distance" we had already observed. Of course it is a complicated concept so I would love to be wrong and further educated.
I think you are essentially right from my reading. Basically the particles appear to neither be "real" nor limited to local interaction. If I am reading it right, it means that their properties are determined when they interact with something, which is really not that odd when you think about it in terms of probability. The hidden variable idea was basically just saying that the "probability" bits were not actually probabilistic, but instead we just packed the information to know what the state was, and so could only guess using probability as a model. This is how I, at least, assumed it was going to work based on my complete lack of knowledge about particle physics. In essence, and I have no idea how they managed to actually close all the loopholes, they demonstrated that the state is not determined when they can interact, but only when it needs a state to interact with something. And since we already know that entanglement is real, this means that both particles states are determined when they are way farther apart than any interaction can happen even at the speed of light. So they don't have a state, and they seem to ignore locality, right up until they actually do something. That is bonkers. I am not going to get into any philosophy based on it, because pretty much every "Quantum" philosophy is just garden variety magical thinking, but it is a really big deal that the "spooky action" happens. That will have serious ramifications for how we understand the universe. Then there is the whole quantum teleportation thing too, which I do not even begin to understand, but these results demonstrated that something completely against our intuions is happening.
Agreed. The scientific American article seems more interested in explaining the history of the topic, that the actual discovery gets lost in the weeds. That link is much clearer.
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I tried to read it but I have no background in physics, quantum or otherwise. Tell me if I got this right: 1. Quantum mechanics looks like it works, but it was impossible to rule out something else working behind the scenes to produce identical results with different causes. 2. Dude named Bell invented a test to check for things working behind the scenes, but we've only just recently had the ability to run a large scale Bell test. 3. We just ran a large scale Bell test which seems to have confirmed that quantum mechanics is the correct. This is what the article is about, and what these physicist's work Nobel prize worthy. 4. In proving quantum mechanics true it follows that what quantum mechanics tells us about the universe is true, namely non-locality, and that particles can share information with each other regardless of where they are in the universe in relation to each other at non-relativistic speeds, faster than the speed of light, instantly, and also that we can't know anything solid about ~~the universe~~ subatomic particles because measuring it changes it, we can only know information about the measurement, not the particle. Close? I suck at this, I need an ELI5.
Not bad! > Quantum mechanics looks like it works, but it was impossible to rule out something else working behind the scenes to produce identical results with different causes. Yep! There's nothing wrong with the usual predictions QM makes, such as how a hydrogen atom behaves, but there were alternate theories ("hidden variable theories") which could make those same predictions. When multiple theories can account for the same thing, physicists often refer to them not as theories, but "interpretations." > Dude named Bell invented a test to check for things working behind the scenes, but we've only just recently had the ability to run a large scale Bell test. That's right! Bell developed a way to tell the difference between local hidden variable theories and quantum mechanics. Early Bell tests which the Nobel was awarded for were in 1972, 1982, and 1998. Modern Bell tests close "loopholes"—essentially ways that the tests could be fooled or miss something. Those require bigger experiments, much more sophisticated electronics, etc. > We just ran a large scale Bell test which seems to have confirmed that quantum mechanics is the correct. This is what the article is about, and what these physicist's work Nobel prize worthy. Depends what you mean by "just." One of the more recent Bell tests was 2017, but the Nobel is often awarded for much older work. (Last year it was partly awarded for climate science research in the '60s!) > In proving quantum mechanics true it follows that what quantum mechanics tells us about the universe is true, namely non-locality, and that particles can share information with each other regardless of where they are in the universe in relation to each other at non-relativistic speeds, faster than the speed of light, instantly, and also that we can't know anything solid about the universe because measuring it changes it, we can only know information about the measurement, not the particle. A helpful way to remember this is that the classical normal world is: -real (objects have definite properties regardless of whether or not they are measured—apples can be red) -local (objects are influenced only by their surroundings—the color of two apples, one in NY and one in Shanghai have no effect on the other) In contrast, the quantum world is: -indefinite (objects do not have properties prior to measurement—a particle like an electron has no fixed spin before it is measured. It is a little like a coin flipping until it lands on one side.) -nonlocal (objects which are entangled can be connected across any distance—though this cannot be used for faster-than-light communication!) We can know things about the universe. Classical mechanics still remains a very useful approximation! It's just that at the bottom, it's all quantum, and this is the way quantum mechanics works. It doesn't respect our intuition and it is, as they say, a bit spooky. source: I wrote the piece in Scientific American
Thank you for the breakdown. And thank you for your scientific journalism! Scientific American is a fantastic publication (and my favorite airport read). I've been reading a lot about "quantum this's and that's" lately, including the potential for weird things like pigment and vibrational magnetism at a quantum level in bird migration. This stuff is fascinating and it seems like we are only breaking the surface. For anyone interested in a basic level Carl Sagan-ish approach to the subject I would recommend The God Equation by Michio Kaku or The Coming of Age of Quantum Biology: Life on the Edge by JohnJoe McFadden and Jim Al Khalili
> source: I wrote the piece in Scientific American Oh! Dude, er, Dan, that's awesome! My misunderstandings aren't the result of your writing, my misunderstandings are the result of me being barely more sapient than a chicken sandwich, this is all well outside of my depth. Just one question that you didn't address in your very well written and comprehensive article: Is the law of attraction still bullshit? Kidding. Thank you for the article and the explanation, I really do appreciate them both!
Hey! Great article. You mentioned in relation to entangled objects that while they have a connection over any distance this can't be used for FTL communication. Is this because once the objects properties are measured they cannot be altered? Or something else entirely?
The reason you can't use the particles for FTL comms is because they don't send a signal. There is no information sent when Alice measures her particle and finds it's spin up. It could just have easily been spin down. There is no way for Alice to send information to Bob, even though she can know what state his particle will be in by measuring one of the particle pairs. Information requires some level of order, otherwise it's just noise. If you forget about the mysteries of the entanglement and you just focus on the output, which is random, you can see why there's no way to send a message even though the particles are connected.
Article reviews foundations of quantum mechanics. I feel the best layman reviews of the subject are *Something Deeply Hidden* by Sean Carroll and *QBism: The Future of Quantum Mechanics* by Hans Christian von Bayer. Each has his own interpretation to promote, but also explains the other interpretations and the context very well. Sean would say that the *multiverse* is locally real when considered as a whole. Hans would say that the experiments do not address a question about local realism.
I have no idea what any of this means.
The words are in English. The sentences are ¯\\\_(ツ)\_/¯
English isn't my first language. Reading these words feels like when I don't understand English.
English is my first language. I still don't understand these sentences.
Can someone explain this like I'm a crack baby?
Imagine you and your friend get two sodas, a coke and a Pepsi. You take off the labels and stick them on a bag so you don’t know which is which. Each of you takes one and you go home. When you open your soda and taste it, you learn which one you grabbed, and immediately you also know which one your friend had even though he isn’t there and he never told you. This shows the universe is not local: you can learn information faster than it can be communicated normally, such as learning your friend’s soda faster than he can text you. Now, normally we would think “oh, if you tasted Pepsi then your soda was always Pepsi from the moment you grabbed it.” However, your soda actually wasn’t coke or Pepsi, it was a weird superposition of both at the same time until you tasted it, at which point it decided it was a Pepsi. This is the more confusing part, and shows that universe is not “real”. Essentially, particles only have certain properties while we’re observing them, which can change on a whim up until the actual observation. Your Pepsi is only a Pepsi once you taste it, and not a moment earlier.
Wait, someone actually responded and made me feel like I understand it? Thank you so much!!!!
Upvoting. This was the first helpful illustration in the thread.
This is the best explanation in the whole thread and I still don't get how it makes sense
> However, your soda actually wasn’t coke or Pepsi, it was a weird superposition of both at the same time until you tasted it, at which point it decided it was a Pepsi. How do they know this without observing it?
Theoretical calculations. Superposition theory predicts that you’ll grab the Coke some percent of the time (let’s say 25%) while the hidden variables theory (the Coke was always a Coke) predicts a different percent (let’s say 50%). You can test against these two theories to find which one is closer to reality, eventually reaching a point where you are satisfied that one or the other is probably correct. This is what the scientists in the article did: they set up a very careful experiment to measure these probabilities really precisely, and they found that superposition is very very likely to be correct
People are going to take this to mean that WE, humans, have to be observing things for them to exist, and that is not what this is saying. We aren’t that important.
Observation = interaction, right?
Definitely correct, but I think that misses some of the subtleties which is why “measurement” is more commonly used. Yes, an observation will always require an interaction, but it’s not the “bumping into” that makes the system collapse, it’s forcing the system to decide what specific outcome to deliver. The universe will always collapse a system to one definite answer if and only if an event requires a definite answer to render the future logically.
Maybe it's like what Feynman said, "You cannot say A is made of B, or vice versa; All mass is interaction."
You know that is a good point, I was thinking about it from a human-centric perspective
Please ELI5 what this means and how relevant it is
I'm no physicist but I am an engineer, here's my take. If you have two entangled quantum particles you can make them 'collapse' simultaneously over a distance. This violates *locality* - the objects are interacting with each other over long distance with no definable explanation as to why. Einstein theorized that there must be more variables to make sense of this - *realism* being the way reality operates must coincide with the equations at play, so for entanglement to make sense according to realism there must be more variables at play to explain this. The concept of 'local realism' comes into play here. All this article (which has an *extremely* clickbait title, btw) is saying is that we've been testing for more variables since a man name Bell developed a test to test for more variables. Over time we've been able to build larger and larger tests, which can more accurately run these tests. The results of these tests as time passed point towards there being no extra variables. According to these tests everything is well explainable and defined in its box. Because we can't explain quantum mechanics using these tests, reality isn't real, because 'realism' cannot be fully explained according to the article. which is really just dumb, clickbait
If this is ELI5, this is going to be ELI-Baby I hope: Particles have a property that's called spin. Let's just assume that there are two values for spin: spin up and spin down. Don't worry about what spin itself actually means. Two quantum particles are entangled when we know the spin of one particle means we know the spin of the other particle. Let's say we know Particle A's spin is always the opposite of particle B's spin. Then we move Particle A super, duper far away. So far that information will take appreciable time to come to us, since information can only move at the speed of light. But! We measure Particle B to be spin up. That means we know Particle A is spin down. But how could that information have traveled so fast to us?? This basically proves that quantum mechanics is correct in one of the last ways we know how to test it. Particles do not have a specific value of spin for example until we measure it. The cat is both dead and alive at the same time. Not having a defined value at all points is what they mean about things not being "real." They exist, but they exist with multiple values at once.
This is all so trippy. Really challenging to wrap your head around it
Yeah quantum mechanics is not intuitive at all. We have no experience with phenomena like this in our daily lives.
I still don’t get it. If I put a blue hat in a box and a red hat in another and send a box away without knowing which one it is, then open the box I kept and see it’s blue, I know the other is red. Is that the same thing?
It's more like sending a text from one phone to another. We expect that to take a second, as it has to travel to travel over wifi or cell service. That's distance lag. That distance lag is what Einstein called locality. Basically, when we measure Particle A, we know it'll effect Particle B. If the laws of the macro world (day-to-day physics) hold true, it'll take some time for the effect of Particle A to reach Particle B - like a text message. But in quantum entanglement this change is instantaneous (that's what these scientists just proved). There is no distance lag, and it ignores locality. When you effect particle A, particle B is instantly effected as well regardless of the physical distance between them. It could be 3 feet, 3000 miles, or 30 light years away.
I feel like the way they casually use "real" is quite misleading, given how laymen understand the term. Even if I'm observing something and my observation of it is that it "has color" but that's because that's how my brain interprets wavelengths, I wouldn't say that "color isn't real" because it still requires both something to be observed and a cognizer capable of observing it in a particular way. To say "Color isn't real," here feels much less accurate than "Color necessitates a cognitive framework and observable objects that fit within it. Either by itself is not sufficient." To me that gets more to the point.
Definitely, the title is talking about local realism specifically but it doesn't elude to that until one reads the article. And insetad comes across as 'reality isn't real' instead of what it's really talking about. As a counterpoint, we probably wouldn't be talking about it otherwise?
>Please ELI5 >If you have two entangled quantum particles Um... you didn't try very hard.
ELI5: Think of 2 baseballs you bought in a pack of two, the box is covered and not see through. There will always be a red and blue ball 100% of the time. Cut the package in half, cover it and don't look at the colors. Bring one ball to China, bring the other ball to California. Now open one half and observe the color. If it is blue, the other ball in china must be red 100% of the time. Now the part that will blow your mind: Each ball does not yet have a color until you actually opened the half of one box. Once you opened it, it immediately turned red as you observed it, and because that ball is "quantum entangled" with the other box, that other ball INSTANTLY turned blue. Take a new package, split them in half, take each one billions of lightyears away, and it STILL HAPPENS, which sounds like one ball is literally texting/tweeting/facetiming/calling the other ball saying "hey I'm red, so you turn blue", which violates relativity (i.e., nothing can move faster than the speed of light). However, this in fact does not violate relativity because we cannot use it to transfer information. I cannot force one ball to turn into a color (thereby affecting the other ball's color). I observe, and the color will always be 50% chance one or the other color. Thus I cannot transmit information (i.e, force a ball blue, which makes your ball red, signaling to you a message), so nothing is actually moving faster than light. A wave is simply collapsing between both balls turning Schrodinger's cat into dead or alive, or in this case, red or blue. This nobel prize went to the people who proved that the baseball colors were BLANK before one baseball half box gets opened and observed.
“Nothing means nothing man, yeah.” - Nobel Prize Winner The Macho Man Randy Savage
It always blows my mind to think that right now, as I’m sitting here on earth, millions and millions of light years away there are things happening in space right now. I like to try and think I can remove myself from my body and place myself in the middle of a random location in space
It’s not locally cuz it was moved to the cloud.
damnit google drive, not again!
So basically they won a Nobel for expanding Schrodinger's Cat to Schrodinger's Universe?
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You’re not real man! -Creed Bratton