Does Quantum Entanglement Allow for Faster-Than-Light Communication?

[@Schottingham]

I love how many of these videos with a question in the title turn out to be "probably not", because you're clearly not setting out to prove these things wrong; in fact you (and maybe most of us) want the answers to be 'yes', but you seem to really work through the science and find that the evidence is just not there. This is the sort of critical thinking we need to teach.

[@chrisbarry9345]

Except that our understanding of sciences laughably and complete. It's openly acknowledged that we can't account for 96% of the effects within the universe. We want to call it dark this or dark that but when you consider how quantum particles are said to pop in and out of fields and combine that with us calling the universe so-called dark, isn't there a lot to say there could be more that we don't know like other dimensions

[@SteedRuckus]

It's sad how so few people actually understand that the scientific method doesn't just bilaterally prove or disprove something tested - either the results are statistically significant in a way that supports one's hypothesis (and further research is necessary for any kind of confidence in confirmation), or you get the "null" result of "something else", which doesn't prove or disprove anything either, it simply indicates that the very specific variable tested is not the cause to your very specific effect (and further research is necessary for any confidence in de-confirming anything). Basically, no matter what the result, further research is necessary nearly 100% of the time.

[@Schottingham]

@@chrisbarry9345 I was careful to say 'probably' because yes, of course there could always be something we haven't discovered yet

[@rockdesertsun8246]

@@chrisbarry9345 I can account for 100% 'of the effects within the universe'..... God.

[@SteedRuckus]

@@rockdesertsun8246 I hope that's sarcasm, otherwise it's a literal logical fallacy to bring in an "argument from the metaphysical" because all rules of logic are now out the window in a debate/discussion. Saying "God did it" is the singularity of debate - once you pass it's event horizon, it's impossible to continue that specific course of logic.

[@BRUXXUS]

I've watched, read, and listened to hours of explanations of why QEC should be impossible, and you effortlessly, finally made it clear. It's so much simpler than I tried understanding that it makes me a little frustrated that it's been so poorly communicated by others.

[@Elmithian]

And I still think we should try to attempt the impossible. If we just decide stay within the boundaries of what we think are the laws and limits, we just end back at the 1899s when patent commissioner at the US branch made the claim "everything that can be invented has been invented." Yes, I am fully aware that lot of stuff is very likely just as it seems, but we still are going to hafta push the boundaries, otherwise, how are we going to fully map out all of said boundaries? Plus, outside the box thinking is what got us the theory of relativity and quantum theories after all. Science should not deal in complete absolutes. If someone tells you "this will never work" they are likely not worth listening to. If they say that "by our current understanding of how things operate it should not work", then they are worth atl lending an ear to. Again, ofc you should ratio your doubts in accordance in science to how well something has been tested, but you should not just wave off left field ideas before you have made sure to make the appropriate tests to confirm that is something that doesn't seem to work.

[@e_neko]

There's still a little problem there. Bell's experiments so far show that entangled pairs are NOT like pre-selected left or right shoes in sealed boxes. The selection really does happen when the "boxes" are opened. Perhaps one day we can find how to exploit this.

[@BRUXXUS]

@@Elmithian Oh, I totally agree!

[@murphyrichard6485]

He did a great job explaining

[@usmh]

Yeah, that's something I've noticed in general. Physicists are terrible at communicating their field.

[@geogabegalan]

This is a very informative video. Quantum entanglement cannot be used for FTL communication, due to its inherent randomness. But there's another thing worthy of note here. The consensus is that information and causality don't travel faster than light. With quantum entanglement, the collapse of the wave function after measuring one particle, is transmitted to its entangled partner much faster than light. But this is not called "information", but "action at a distance". But information and action have blurred boundaries between them. Every exchange of information involves a physical action. For instance, if I get information through sound waves, the waves have to do the action of vibrating my ear-drums. And if I use my arm to lift a book, I am also sending it the information to alter its spatial co-ordinates. And it is not said that it travels "faster than light" (well, you said it in the vid, and kudos to you for that, but some others don't), but that its "non-local". It seems to me that these distinct terms for quantum mechanical phenomena only obscure the simple fact that: We have discovered three speed limits in nature. 1. The speed of sound in any given material, which is the natural speed limit of mechanical waves in that material. Nature has many random sources of sound, like thunder. But we can use sound in a non-random way to communicate. We also surpassed the speed of sound with supersonic technology and EM waves. 2. The speed of light in the vacuum. This is the natural speed limit for matter/energy travelling relative to the reference-frame of another system of matter/energy, as well as information and causality travelling between systems of matter/energy that are not quantum entangled. Nature has many random sources of EM waves, like lighting. But we also learned to harness EM waves for communication. We also learned to detect random sources of gravitational waves, though we can't harness gravitational waves yet. The only source of faster then light transfer of information/action that we know of so far is number 3 below. 3. The speed of transmission of information/action at a distance, from one quantum-entangled particle to its partner, to maintain the entanglement at a distance; as well as the collapse of the wave function from a measured particle to its entangled partner. Here, the entangled particles are natural, random sources of...whatever it is that is being transmitted between them to maintain the entanglement. A classical analogy to quantum entanglement might be acoustic resonance. An even closer analogy might be the *synchronised*phase*opposition*of*two*pendulum*clocks* (you can google it, its interesting). Here, the means by which the synchronisation is maintained are: the "non-local hidden variable" of acoustic waves transmitted from each clock to its partner through the substrate (say, a wooden beam) to which they are both attached. If we can identify the "whatever-it-is" that is being sent by entangled particles to each other, to do action at a distance between them, then we can dispense with quantum entanglement, and build a device that uses this "whatever-it-is" to communicate faster than light. Have you made, or are you planning to make a vid about interpretations of QM that involve non-local hidden variables ("whatever-it-is"), like Bohm's pilot wave, and their possible use (or not) for FTL communication? It would be interesting to hear your take on this.

[@StevenScienceNTech]

Hi, I built a simulation setup that demonstrates FTL communication. Maybe can check that out? kzbin.info/www/bejne/noq9goetYqeig6csi=lcKdBBlY2g8Lsfwf

[@jordanwhisson5407]

Plenty of things travel faster than the speed of light including some galaxies

[@KazuDiabolis]

@@jordanwhisson5407 cap

[@Seehart]

The notion you refer to in 3 has a dubious premise, that "collapse of the wave function" is a "thing that happens". While that is presumed in the Copenhagen interpretation, there is no scientific support for this premise. It's not in the mathematics of QM. If collapse is not a thing, then there is nothing to transmit. Spooky action at a distance is an illusion. After omitting pilot wave theory and it's relatives for various good reasons, we are left with Many Worlds, which is simply nothing more than QM taken at face value without adding any nonsense about collapse of the wave function. When Alice measures the spin as Up, absolutely nothing whatsoever "happens" to Bob's electron and nothing is transmitted. What we do know is that Alice shares a world in which Bob has a Down electron. Or to put it another way, Alice and Bob are in a superposition of states such that Bob-with-up-electron can only encounter Alice-with-down-electron an vice versa. Collapse of the wave function, should be regarded as an anthropic subjective experience rather than a physical phenomenon, in the same sense that finding yourself here and now is an anthropic subjective experience.

[@talharehman3664]

@@jordanwhisson5407 That's not velocity. They are just receding away from us at faster than light speed due to expansion of space but they are not moving/traveling faster than light. You've got the wrong understanding of that notion

[@TheInterestingInformer]

I always click on these videos knowing the answer is gonna be no, but always hoping I’m wrong

[@mjbarge]

Finally! An explanation I can actually understand. Your ability to communicate very complex ideas in such a clear and understandable way is by far the best I've come across. Keep up the great work!

[@nickduplaga507]

If something is reacting at faster then light speed there is energy traveling at faster than light speed. Should be common sense. Also wormholes are possible in physics. Space can move time faster than light. Black holes singularity universe sees black hole frozen from aging, but it’s only perspective. The black hole can experience the universe aging faster into infinity even experiencing events that the universe can’t yet experience. The concept of negative energy that NASA claims is created by gravity.

[@jaywulf]

All that + lovely voice!

[@DomovoiJr]

Causality dictates that no one has finished this video yet at the moment I’m posting.

[@PafMedic]

Im Watching At The Moment,But Was Thinking The Same Thing😂😂😂

[@wzrd7023]

what if someone watches it at 2x speed

[@TennesseeJed]

@@wzrd7023 ...and ½ speed on another device.

[@danieladmassu941]

That just means Patreon members get to enjoy miracles. 🤔

[@jasonfaerwald]

You can if you set the video playback speed to FTL

[@friskeysunset]

OutSTANDING work here. You took the whole thing apart and put it back together for me to understand that Einstein's limit is really about causality and the nitty-gritty of why all of my little fever-dreams for FTL communications are impossible using entanglement. In half an hour. Bravo. My heart is broken, of course, but you let me down as easily as anyone could have, and your closing remarks about facing reality as it is was right on target. Thanks.

[@cyberfunk3793]

What we observe in quantum entanglement isn't possible according to relativity. The fact that we can't use it to communicate doesn't change that, if the particles can use it to communicte faster than light (as our observations currently seem to show) is enough to violate relativity. There seems to be no phycisist that currently can explain what we observe in QM. They don't know and can't say.

[@Skrzynia]

@@cyberfunk3793 Wrong. Nothing is violated here. The information can not travel faster than light and as the video explains, you can't send any information using QE even tho its faster than light. Its "nothing" that travels faster than c

[@cyberfunk3793]

@@Skrzynia Special relativity is obviously violated by entanglement unless you think you know better than Einstein who wrote the theory. Einstein obviously agreed QM violated the principle of locality, that is the reason why the EPR paper came to be. The principle of locality means nothing (energy or matter) can travel faster than light, so no interaction can happen faster than that between A and B. It doesn't say, that we just can't use it to send information, that is an excuse people nowadays use when they don't wish to accept reality and that local realism and specialy relativity has been refuted empirically. The only way to avoid this conclusion is superdeterminism, so unless one is actually advocating for that they can't imply entanglement doesn't violate local realism. My personal opinion is that superdeterminism is absurd and really a childish cop out for people unable to follow the evidence when it takes them to inconvenient conclusions.

[@vladimirfilipovic5845]

You finally helped me understand why QEC should be impossible, you have a knack for explaining complex things , thank you, keep up the good work!

[@glitcherade1482]

It's the first time I actually understood entanglement, very well done mate, I always love your way of explaining.

[@immortalsofar5314]

Why did nobody else explain the shoe box? That's all they have to say!

[@gravoc857]

@@immortalsofar5314 Because the shoe box by itself doesn’t do it justice. People still get caught up in thinking about “well, both know that the other has the corresponding pair, so they have a full set!”. This indicates a thinking that some how you can come to a forced measurable result. Kipping explained beforehand that it’s entirely random, and that no matter what you do to the entangled pair, it always results in a randomized dice roll that provides no relevant information if you only have half the set. In other words, if you get a left shoe. You don’t know that you have a left shoe, unless you can see the data of the other party. The shoe is only a left shoe, relative to the other previously entangled particle. Without knowing the state of the other particle, you’re left with an annoyingly undefinable particle. This is also where the Heisenberg uncertainty principle comes in. Measuring for one vector, increases the uncertainty in another vector. Measure it’s location, and the speed becomes blurry. Measure the speed, and it’s location becomes blurry. You need multiple measurements, but only one measurement can be applied before the super-positioned entanglement ends.

[@ologhai8559]

just put it in transparent shoebox 😂

[@matthewfrost3677]

@@gravoc857 it sounds to me like quantum entanglement is not FTL in its action. It sounds to me like entanglement just imparts opposing Quantum fields causing them to collapse in the opposite directions when observed but not transmitting any information instead revealing their pre determined bias

[@gravoc857]

@@matthewfrost3677 That’s what I used to think. That the information is perfectly symmetric. We need to remember though that measuring one particle will instantly reveal the nature of the second particle, no measurement required. If you and I’s assumption was correct, an entangled pair would require two measurements.

[@RazyMon]

If any interaction with an entangled particle collapses its state, then there's no way for Alice to observe changes without affecting the state of the pair. In other words, if there's no way to observe (let alone affect) a particle state without collapsing it, this system is pretty useless as a mean of communication.

[@NefariousKoel]

To me, that seems like the real kicker at the base of it. If the receiver has to monitor for changes, then it's already collapsed by the receiver. The whole transmit-receive concept won't work.

[@VikingTeddy]

I don't think I completely understood, because it seems you can keep both particles on a perpetual double-slit experiment, and only collapse one when you need to send a bit. So Bob and Alice agree that at time t, Bob will either take a measurement of the particle (meaning a one), or leave it alone (meaning zero). So if Alice who is watching the particle going through the slits, sees a collapse at time t, she knows that the message is one. What did I miss?

[@Ijusthopeitsquick]

@@VikingTeddy My thoughts exactly. Collapsed or not collapsed is just as good a binary system as left/right or up/down. All you would need is an agreed frequency. I'm sure I must be wrong, but I'm too dumb to know why.

[@spacenoodles5570]

@@VikingTeddy I think by doing the slit experiment you will collapse the particle, as you're measuring its state

[@VikingTeddy]

@@spacenoodles5570 The slit experiment doesn't collapse the wave, otherwise we'd never see interference. I'm sure there are other ways of checking if the wave has collapsed which don't need such a complex setup. The experiment itself isn't difficult, but isolating it from all other particles is quite the challenge. I'm hoping someone with more knowledge stops by so we'll know how the idea doesn't work. Or if we can go pick up our cheque.

[@doggonemess1]

I am really proud of thinking up the "tachyonic telephone" when I was younger. I only discovered that someone had dreamed it up almost 80 years before I did, but I love the theory. Using tachyons, which may travel backwards through time, you can send a message to a far away receiver. They would get the signal in the past, relative to the distance light takes to travel that distance. I can form the idea in my head, but can't explain it. If you look up the term, someone else can do a better job than me.

[@afnanejaz9297]

so technically tachyons don’t actually travel backwards through time, time is always moving forward with entropy and entropy can only be reversed by chance for split seconds at a time and i have no clue what im talking about why are you reading this

[@WeRemainFaceless]

Tachyons don't actually exist though. There's zero evidence to even remotely suggest their existence. But in reality, if communication with the past/future was actually possible...Tachyons wouldn't be needed. Simple Photons would be. You see, Photons, being massless, always travel at the speed of light. We know that anything travelling at the speed of light cannot experience time. From the perspective of the photon, there's no causality. Its emitted, travels and arrives instantaneously. Which then raises an oddly interesting point. If the Photon does not experience causality, in the classical sense of cause-effect, then all events that a photon is subject to, influences the photon throughout it's entire existence as we perceive it. So, observing a photon today, will have influenced that very same photon in the past. Scientists have proven this via the Delayed Choice quantum eraser experiments. The sad fact however, in order to observe such a change in the photon in the past, you must first know what change you have actually made to it. So the only way to decipher the information, is to first know what information you're trying to decipher. Hence, its not possible to send information faster than the speed of light.

[@dananorth895]

@@WeRemainFaceless the photon follows a null geodesic path....interestingly this is how information gets around the universe. On the photonic level of reality it is instantaneous or synchronous.

[@williamkoch1947]

9

[@stewiesaidthat]

@@WeRemainFaceless the very fact that photons are massless means they have a zero decay rate and thus don't experience 'time' aka change. Photons can travel at a speed anywhere between zero and infinity depending on the permeability and permittivity of the space it is traveling through. Nothing can go back in time because causality is instantaneous. Once an event takes place, it can never be changed. You can however 'witness' the event again in another location in space. The speed of light is the fastest information can be transmitted but you lose information with distance so the only thing you will 'see' are specs of light. You can't really do FTL though because electromagnetic waves are energy waves and the universe is made of energy. You would have to enter hyperspace or subspace where travel is faster than normal space.

[@dmsoundcollective6746]

I don't know how to express how wonderful these videos are. I guess I can only say thank you David!! I love what you're doing

[@9fmradisapratama]

This is the answer I hoped from you. As a person who failed at physics I can't do anything but silently watch physicists and the other people discuss the formula and interpret it. My question is always "How can you define a useful communication while neither of you know it or not needing to know it the first place since it breaks the moment either of you measure it and the opposite of you not knowing it breaks yet which is simply "sending information without knowing that information from the first place". How can you have a good communication while neither of your observations needed?" And this might be rooted from my ignorance since I don't know physics and your explanation corrects all of my misconceptions of that although I have the shared answer that is a solid no, or at least not enough. The difference is that my argument is filled with misconceptions and ignorance while you have valid reasons.

[@guillemsegurapascual8968]

y yoo😮😮ooy

[@jasoncravens1124]

Nah, you're correct, or very close anyhow.. Schrödinger's cat, sort of ...IS an observation required? Entanglement is, specifically, Feynman diagrams. Two-slit, as I'm sure it referenced. Amazing stuff. 👍

[@jcevans16]

I'm no rocket scientist, I can barely wrap my mind around what you're saying, but I am a science nut, I love all things space related. I love your presentation, for lack of a better description I find this video soothing? Its like Relaxing and learning at the same time. Sorry if I'm weird.

[@BTScriviner]

You're not weird. I get the same sense when I watch Dr Kipping's videos.

[@RyanEglitis]

It was cool to finally find someone who would delve into all the what-if's of FTL/entanglement attempts. One thing I think that could have helped was to clarify how it doesn't really help to collapse a state as a signalling mechanism either, as there is no way to _see_ that a state has collapsed without observing the particle. And of course, observing the particle collapses the state.

[@awvscbsteeeerike3]

These videos are awesome. Also, wish I had read this comment before taking 30 mins to figure that out on my own. Ha.

[@AndrewJens]

Can't information be encoded by Bob delaying the second observation after his first? E.g. If he waits 1 second after the first observation (before making his second observation), then it's a "1" and if he waits 2 seconds then it's a "0"? Alice then doesn't have to care about spin direction, she just has to note whether it's 1 or 2 seconds between her first and second disentanglements happening. (I know nothing about all this, so sorry for wasting time if it's a nonsensical suggestion.)

[@RyanEglitis]

@@AndrewJens No, because again, you can't tell if Bob has collapsed his state. If you look at a particle _after_ he observed his copy, you see a random spin (which later you could confirm was the opposite of what he saw). If you look at a particle before he observes his, you see a random spin (which Bob can later confirm was the opposite of what he later saw). The two states look the same to you: you saw a particle with a random spin. You can't tell if he's observed his or not - it's not like the particle turns red or something when Bob observes it so you know it's go time. You're not looking at it when Bob observes his copy - how would you know anything happened?

[@AndrewJens]

@@RyanEglitis Ah, so I'm not understanding it at all (but thanks for taking the time to reply). So how does Alice detect the collapsing of the spin state of her particle (assuming she's a keen observer and is watching continuously)?

[@RyanEglitis]

@@AndrewJens It's my understanding that you would detect it by interacting it with some other particle (i.e. electron, photon) and then multiply up the result to something human scale. "Observing" something is just a way of saying "interact it with a bunch of stuff so that we know the state of it (at the time of the observation)". It's part of why it's hard to keep entangled particles - you need to keep them away from _anything else_ that could interact with them. Even if we don't _see_ the result, the entangled state would get lost.

[@mxbishop]

This has got to be one of the very best explanations of quantum entanglement I've ever seen posted on KZbin. Thank you. The important take-away here is that entanglement is non-local - but even so - it does not violate causality. But why is it non-local? I think one area that needs more theoretical exploration is the idea that spacetime itself is quantized. If we imagine spacetime as quantized - it means spacetime particles (or whatever one wants to call them) can exist in superposition, and that means spacetime particles may exist as entangled pairs. So it may be the case that a pair of entangled electrons, derive their non-local status, because they exist within the same particle or envelope of entangled spacetime. The idea worth exploring is that there may be other dimensions that we do not observe directly due to the quantum nature of spacetime, and as such, what appears to us as non-local effects that happen faster than the speed of light - are actually demonstrating to us that spacetime itself, is entangled. And perhaps the spacetime entanglement involves more dimensions than we can directly see. So in this model of spacetime, "Spooky action at a distance," is not really happening at a distance. Instead, the effect is happening within the confines of entangled spacetime. What appears to us an instantaneous communication between a pair of entangled electrons that are far apart - is actually happening in the same region of space - that is an envelope of entangled spacetime. Entangled spacetime, if it exists, could have enormous implications for all of physics - and may even, propel physics to a new foundational understanding of the universe. Please think about quantized spacetime, and its close cousin, quantized gravity, as a promising new direction for physics. Some thought experiments are needed to complete this picture. Please carry on.

[@sandip-g2m]

Such a lovely video with amazing closing comments that are applicable for not just the context of this video, but life in general. Thanks for all your videos. Really love the way you explain things with such ease and fluidity

[@Benson_aka_devils_advocate_88]

This is something I've pondered ever since I learned about quantum entanglement. I've spent many nights thinking about the ways it may or may not work. I'm really glad you touched on this topic and I can't wait to see what your take is on it!

[@Brendy733]

I’m shocked I haven’t found your channel sooner. It’s quickly become my favorite space channel on YT.

[@skizmo1905]

It's pure trash... why are you so happy to find it?

[@Brendy733]

@@skizmo1905 ok 👍 why do you think it’s trash?

[@savage22bolt32]

I could not put up with the annoying background noise.

[@Brendy733]

@@savage22bolt32 I didn’t notice I’ll have to see for myself

[@savage22bolt32]

@@Brendy733 i thought the subject matter would be interesting, but the music killed me.

[@EricMalette]

I read this terrific sci-fi series called The Gap, by Stephen R. Donaldson. I was in my teens, so I had no notion of the idea of entanglement or quantum. In the books the aliens called the Amnion, had this crystalline device that allowed them to communicate not only faster than light but essentially instantaneously. The shock of the human characters when discovering this was truly chilling. They could place their ships where they needed to be without dispatching a gap courier drone to cross the void. Truly hideous.

[@AndreaSzabo7171]

Isaac Asimov. + Philip K Dick. 💘💘

[@dominicmillerca]

After listening to a lecture by Alain Aspect two weeks ago, I've decided to attack the subject with the book "Introduction to Quantum Mechanics" by David J Griffiths and Darrell F. Schroeter, it's pure food for the brain. Your video couldn't be more on target with the topic. As usual, very interesting and clear with a great sound quality and beautiful video editing. 👍

[@knucklesamidge]

That book is pretty great it seems. Do you know the maths?

[@CHIIIEEEEEEEEFFFFSSS]

Every single time I thought of a potential solution, you said it right as the thought was entering my brain, in the same order I thought of them.

[@rosaeruber225]

what did you expect? experts know what they're doing.

[@CHIIIEEEEEEEEFFFFSSS]

@@rosaeruber225 he's positing it as a thought experiment. I was playing along. I didn't really expect to think of a solution while I sat watching a youtube video. It was more that I had a repeated series of "why not _______?" just as he started to explain that very solution each time.

[@malachi-]

@@CHIIIEEEEEEEEFFFFSSS It's called, human nature.

[@thagrintch]

David, I can't get enough of your channel. This was one of your best topics. At this rate, you are going to hit 1 million subscribers in no time. Thanks for the great insight into nature and the cosmos.

[@CoolWorldsLab]

Thanks so much! This episode took a lot of work so pleased you enjoyed!

[@canadianvideos6094]

@@CoolWorldsLab I had also asked about this topic/possibility after your previous video. Thank you very much for providing such an excellent explanation! Love your channel, thank you for all the hard work!

[@Mccade1]

One of the great videos on KZbin, great job dude!

[@jacobmalof]

Makes me think of the measurement problem. Everything that’s going on in double split before the electron hits the screen, where the measurement of the position actually takes place, the wave seems to collapse. It chooses a position to narrow itself down to. The act of measuring the wave changes the wave. In the interference pattern of the double split, we know the collapse is not random. The electron is very likely to be where the wave is strong and unlikely to be where it is weak. There seems to be a correlated anomaly that we haven’t fully grasped yet. I hold out hope for additional breakthroughs in the future.

[@xxmeanyheadxx]

energy is everywhere all at once. light is energy. to attempt to grasp an infinitely small moment of light is futile (see; achilles and the tortoise). however, we perceive an infinitely small moment of time at any given time. this is only human perception. the light is always there. the patterns are always there.

[@absynthetheartist]

It's double slit not split.

[@Parabol1Parabola]

This is literally the best channel on KZbin

[@darwaynelynch]

Two things come to mind. 1. Deeper research into understanding how to detect if a particle is entangled or not … if this can be solved we’d have a way to communicate FTL. 2. Entangled Particles are obviously communicating somehow, digging into the how could be the medium we use for FTL communication

[@wesjohnson6833]

Cannot detect whether one is entangled. And the first measurement breaks entanglement. It is not obvious at all that they are communicating. In fact its fairly obvious they are not.

[@Merilix2]

2. How is it so obvious? In my opinion it's much more convincing they share some kind of information but we just don't know how exactly yet. Bell-Inequalityl is targeting determinable particle behavior but those quantum objects aren't just particles. They are more like waves which have to be described with complex matrices.

[@wesjohnson6833]

@@Merilix2 Not waves, but one wave. Being entangled means they share a single wave function. That single wave contains two particles worth of information in the possible selections of (up/down) and (down/up). When one particle is measured it collapses that single wave function for both. They do not need to communicate. They have no choice but be opposite as there is no (up/up) or (down/down) possibility to randomly measure.

[@Merilix2]

@@wesjohnson6833 Well, the one wave function you are talking about is just a probabilistic math model. This wave function does what every function about probabilities have to do if you get measured results. The model collapses from uncertainty into (partial) certainty. In my opinion its just misleading layman's if the word "collapse" is used like something really happens remotely at that moment. I think, entanglement is about the contrast between uncertain principle and conservation laws. I'm pretty sure, the Copenhagen interpretation as good as it really is is not the end of the story yet.

[@wesjohnson6833]

@@Merilix2 I agree about Copenhagen. Not advocating that as gospel. Of course the wave function is a model. Some argue it is physically real (like many worlds advocates), but even if s bookkeeping device, it does seems to model something physically real. "Collapse" is another term we use for lack of a better term or model. With caveats I think we can use them meaningfully. That said, it is true that only one wave function is needed to completely describe the entire system. And there is no uncertainty about the system, just the parts. They are entirely random which is a necessity for a maximally entangled system. I just noticed reading through the thread that you were replying to the initial comment and not mine. lol. Oh well, sorry 'bout that.

[@moxxy3565]

Just to clarify, it's not the actual observer that causes particles to behave differently, but the fact that you can't measure something without applying some force to it

[@WilliamDeanPlumbing]

This is exactly why I Proclaim that we have never been visited by other life forms, they have the exact same problem that we do, the vast distances and the slow speed of light prevents any survivability to make it from point A to B.

[@silvergreylion]

When referring to light, you probably mean transverse light, or transverse EM waves. Longitudinal EM waves propagate at practically infinite speed. It's just that they are much fainter, so very hard to pick up, and in the development of radio communication since its inception, everyone just assumed longitudinal EM waves didn't exist. They do, but it takes a spherical antenna for transmitting, and very sensitive equipment AND a spherical antenna, for receiving.

[@silvergreylion]

@@pereirahawk This is currently being researched. The research hasn't been published yet, but the speed would be the reciprocal of the Planck constant, so ~1.5x10^33 m/s.

[@sraldleif]

​@@silvergreylion I'm currently researching how to turn my hot tub into a time machine. I haven't published anything yet though, so you'll just have to trust me when I say it's totally legit.

[@theifthenist]

We are apes, one foot out of the trees. Yet we have, OURSELVES, proven theoretically the reality of wormholes. Why is it so hard for not so smart individuals to believe that in a universe with COUNTLESS planets able to support life, there would be one (or one million for that matter) life form that figured out how to use the Einstein/Rosen bridge wormholes practically? The arrogance of some simple minds to think that we "apes" are the pinnacle of intelligence in the universe is hilarious. New discoveries in physics happen every day. Smh.

[@JB52520]

Biological survivability isn't a problem for a machine, or a being made of information which a machine might host. Either could decide to pause any sentient parts of themselves for the journey. The expense would be enormous because it would lose contact with its civilization forever, unless the whole civilization also pauses itself. But if a civilization does so, the loss of subjective time could be vastly greater than we would lose. It would be a pointless leap toward the end of the universe, while greatly increasing the odds of a disaster happening within any of their lifetimes, if that concept applies. However, a machine might bring a whole civilization with it. It would lose contact with an instance, but have a whole divergent instance to thrive within. This would have the benefit of creating redundancy, such that any lost instance could eventually be replaced, possibly recreated to a degree with any surviving information. Long story short, everything is different when you're not biological. Unless the calculated being is a simulation of a biological entity. But the spirit of "everything" being different still applies.

[@antanaskiselis7919]

When you've started laying out examples I was hoping for mass effect. Thanks, nailed it. Also, thanks for the video, not long into it yet, but I was looking forward for something like this for years I think at this point.

[@a-cv8396]

Very nice video as always Cool Worlds. I really enjoyed that many scenarios were explored and references to how some of these promising concepts were embraced by popular science fiction as a plausible solution for communication across vast distances. Something to understand about the current state of quantum mechanics is that the act of measuring is never passive and becomes deterministic of the answer we will get. In most other domains of science our measuring tools manage to have a minimalistic impact on what is being observed. But in the context of quantic mechanics there is no sight, what we try to measure is so small and the way of measuring is throwing particles against the particles we are trying to observe to see how they bounce off. Perhaps everything will be reconsidered if we find a technology to measure the quantum states without as much interference. I'm already impressed that through statistics of infinitely repeated experiences the quantum mechanics science is able to establish causality when every observation is destructive and deterministic of the state being observed. I find it interesting to think that anything FTL could however break causality. If we used a theoretical wormhole to send a mere Lightspeed communication through a distortion of the spacetime elevation map, would that be breaking causality ? The speed of light appears to be in a way the speed of time. Riding a photon, one wouldn't experience time at all. Any particle without mass also seems to be traveling at this speed, and so do gravitational waves. Electromagnetic waves are slightly slower than the speed of light. It seems like a possibility that the perception of time could be an emerging property of the interaction with the Higgs field. That anything with a mass is dragged through the ever expanding time dimension and able to perceive it, perhaps akin in the same way that gravity holds galaxies together in an otherwise ever expanding spatial universe. Could dark energy be expanding all of spacetime and our perception of time be a mere side effect of gravity on spacetime?

[@CandidDate]

Well, yes and no. Make a guess and you're correct.

[@TheRotnflesh]

I love the entire breakdown. Continuing with "mass dragged.." One thing to remember, always, is that we are made of the same crap we see when we look out 'there' in space. We are designed adjacent to the circumstances of our environment: Our genetic code is adaptive due to climate changes, our forms are a collection of atomic-scale fusions, cellular formations, and biochemical reactions. Systems within systems, like a galaxy itself. We are finding that the fundamental substrata of our universe of probabilistic. Maybe its a gigantic mind, and we are part of a gigantic, cosmic neural network? Being so aware of the system that we can modify and adapt it utilizing the same sentience that makes it up? ;) After all, what we are to a human brain would be somewhere in the center of the nucleus of an atom in a neuron.. That was off-topic. What I was getting at is that we only observe the universe at a rate we were DESIGNED to. Universal time dilation is totally subject to the framework of the observer. In this case, average humanity. That observation has 2 obvious possibilities: That what we see is all there is and is subject to external events involving light (which can shock the observer's system when what we see does not align with our contuinity of events from a personal framework), or what we see is defined by what we expect to see. This latter idea is vain, and points towards man's egotistical idea that we are somehow separate from the energy we are made of; essentially, god beings. At least, simplified, this is how I interpret it. FTL is possible in theory because existence just is. We are the instruments ill-equipped to be somewhere else from 1 moment to the next. Its a material limitation of our very design.

[@med2904]

We already have a way of measuring the quantum state without interference. It's called "delayed choice quantum eraser". Check it out. This experiment proves that it's the act of observation, or at least the information about a particle becoming available to the universe that collapses the wave function. An entangled particle somehow "knows" that its partner will be measured in the future and collapses its wave function retroactively. So the interaction during observation would have to break causality for the non-measured particle to "know" that its entangled partner will be measured in the future.

[@wwatse]

I literally asked myself this question the very first time i heard of quantum entanglement Thanks for this video

[@shingnosis]

Thank you, this is something which has been bugging me a lot in sci-fi. Entangled particles are like having two pieces of candy that look the same, one is sweet and one is sour. Then you give one to a friend and he travels to the other side of the planet. If you eat your candy you'll know what flavor you got, and what flavor your friend received. But it really does you no good other than that. If you want to talk to your friend and ask him if he liked his candy you still have to use your phone. And obviously you can't change the flavor of the other candy by doing anything to your own candy.

[@iurlc]

You are right - the problem is that the mystic far distance influence was "proven" with Bells inequality. But this inequality is based on set theory. But every measurement is an energy transfer. And for this vector equations must be used with basic electrical formulas. And then you will get the right answer, even if you assume the two are paired in the beginning of the experiment - not only at measurement time.

[@mohamedaminehenchir297]

What if you had prior information that your friend doesn’t like sour candy and both agreed to eat the candy no matter what, wouldn’t that be reliable information?

[@davideggleton5566]

@@mohamedaminehenchir297 -- Still doesn't communicate anything new between each end of the entanglement, unfortunately

[@Joopfyi]

What if one candy is deadly and the other candy not. The result of quantum entanglement will still be a 0 or 1 when measured. I think there is very viable information in that case. So then you could say: After eating the candy you must do the same candy experiment with your neighbour. That means if we measure if person A is still alive the neighbour of person B does not know anything about a candy. So giving extra tags to a case before measuring will create a lot of good information.

[@ryanduckering]

K, but what if you had a bag of quadrillions of pieces of sweet and sour candy and you ate them on your end in a very specific order to communicate a binary code?

[@Jimmy-B-]

Now I understand, always thought you could force a spin, but that was cleared up, thanks!

[@robertwcote]

This is really well done, you guys. Great work. At the beginning you alluded to communications between distant outposts of an interstellar species. This is something I've been wondering about a lot lately and would love to see you discuss it at some point. The main thing I struggle with is the assumption that we would communicate with humans who set out to settle an extrasolar planet. I mean, would we actually? At some distance, the latency would make it almost pointless, right? What sort of information would we share with a colony a light-year away? 10 light-years? 100? It's natural to assume we'd have communications, but when I actually stop to think about it, I'm not so sure anymore.

[@LWT80]

Taxes bro. All we need to do is set up a colony and the IRS will figure out the FTL communication problem in no time.

[@zachb8012]

As far as the nature of a conversation is concerned, listening, processing, responding. The delay would severely limit what could be communicated in that sense. Nevertheless I would imagine the basis of communication between distant colonies would consist of a constant two-way stream of art, media, and scientific knowledge. The expectation wouldn't be the recipient colony would respond and convey something meaningful, rather that all parties would continue sharing their culture and information.

[@brunospasta]

If we would do this one day and the rules of physics we know today still apply, I would guess there would be multiple different species of humans at some point as we'd evolve differently depending where we are. Communication with other human "species" would be more of a fun thing to do, but wouldnt hold too much purpose at this point.

[@jackwilson5542]

There is no speed limit on communication. It is a myth perpetrated on purpose of keeping this world "in the dark" aka. not known by alien civilizations. (Type 2 civilizations and higher don't communicate on RF spectrum) If there is widespread belief in there being a limit, nobody/few will research possibilities past it. I personally worked on Special Access Projects, so I know this for a fact.

[@protorhinocerator142]

The conversations would be highly relevant if we also had FTL drive to get us to those planets in a non-ridiculous amount of time. Using rockets or generation ships? Forget it. Star Wars or Star Trek? Now you're talking.

[@harryshriver6223]

As someone famously once said, you got to play the cards that life feels you sometimes you win sometimes they lose but at least you're in the game

[@Jagdishtemkar1]

I thought that we can dictate which spin we want the particle to be in, and that is how Quantum Computing works. Now I need to revisit that again.

[@larsnystrom6698]

@JAGDISH TEMKAR We can control the spin of particles, for example electrons, but then we get bits, and not qubits. So not quantum computing, just computing. The trick with quantum computing is to compute with bits in superimposed states, i.e., Qubits, until we read out the result at the end.

[@WRanger87]

@@larsnystrom6698but if you can force spin-states, as a bit, why can’t quantum entanglement work to send bits of information?

[@I_SuperHiro_I]

@@WRanger87send it how though?

[@robnathan7690]

Thank you for all this content. I agree with others, you are truly inquisitive, accessible, willing to admit when we Don't Know, or even more importantly, willing to question what we think we know! 🙏🏼

[@spacescienceguy]

Cool to see 'ansible' mentioned, as it's the first thing that came to mind when I saw this video title! I came across the concept of an ansible (device for FTL communication) in the Ender's Game series, but it was an homage to Le Guin's work.

[@Bertydude]

I have the solution : You dont actually have to measure spin. You have two entangled pairs as you collapse one, it sends a 0 and if you collapse two, it sends a 1

[@lorackavery3225]

There's now way to determine if the entanglement has collapsed. If there were, then you could just use one set of entangled particles. If it's collapsed then it's 1. If not, then it's 0. He explained why this doesn't work.

[@D33zNutzOnyaChin]

Best explanation of this topic I've heard, thank you. Not only that, your final thought went beyond the science and was just a great lesson for life as a whole. Great job 👊🏿

[@jarradgray56]

Wish I had you as a lecturer at University, your ability to communicate and break down extreme complexity into simplified terminology, then bring us(the viewer) back up to the level of understanding through step by step learning to give us understanding of such complexity is brilliant..(I hope that even made sense) No offence to the seriously intelligent people out there with in their specialised fields, but not every PHD, Dr, or Prof can communicate with the masses.. At university I was told by a Doctor of Chemistry that "a Dr knows a heck of alot about very little". 😊 it took me a moment to realise how true that statement was.

[@alals6794]

haha......"a Dr knows a heck of alot about very little". Great quote

[@stevencoardvenice]

You have to truly understand something in order to explain it. There's a mark Twain quote. "An expert is just some guy from out of town"

[@rolobotoman]

"Wish I had you as a lecturer at University," me too, but unfortunately, you can't put lecturer at 1.75x playback speed.

[@BayouBushcraft]

Thank you for your hard work with all these videos. Best science content on KZbin

[@tinkerman-q]

I revisit this episode from time to time and I realize something new every time. This is not only a particle physics lesson. It is a life lesson. Thank you again for the inspiring words. Thanks for remembering me that indeed it is possible that as bad as the hand I have been dealt with, that what comes out of it may still be wonderful. You are someone that I would love to have the opportunity to sit down with and engage on a deep conversation. You have a type of mind that is not accessible to me, unfortunately.

[@MagnusErikssonIsMe]

Really awesome video! Really easy to follow and understand, even though the concepts are advanced. I do realize that most things might be and "over simplifications" when talking about quantum physics etc, but it did give a bunch of "aha"-moments. It's very appreciated!

[@mon573r6]

It's definitely a nice video. I don't necessarily agree the assertions, but fun to watch nonetheless. Also If your still murky on any of the concepts, feel free to ask. If I notice the comment I'll answer. Not sure I'd consider myself an 'expert' but I've always loved stuff relating to Quantum mechanics and/or Theoretical mechanics with practical applications. ^.^

[@PhilipSportel]

One solution I've never seen discussed before is if Alice and Bob agree on a schedule, planning in advance which particles would be measured when. By agreeing to a tempo (and maybe having trillions of entangled particles, error correction codes, etc...), they can both know that the particle they're measuring was intentionally set to spin in a certain direction. They downside is they'd be forced to 'burn' their communication particles continuously, whether or not a message needs to be sent, but this would simply be another kind of fuel, something to be replenished when needed.

[@Scott_Raynor]

But how does that transmit information? Whatever Bob does, Alice will either see an up or down spin - Bob can’t affect which one it will be.

[@zachhoy]

@@Scott_Raynor just the timing alone can be the information

[@Scott_Raynor]

@@zachhoy how?

[@TheChzoronzon]

​@@zachhoy a pre-arranged timing transmit no information

[@TheChzoronzon]

"they can both know that the particle they're measuring was intentionally set to spin in a certain direction" No, they can't if the spin is random until measured. You can't pre-determine the spin before the measure, that's precisely the key point. If you could, FTL transmision would be trivial.

[@timrundle-wood4420]

Another incredibly thought provoking video, thank you so much David for the time you put into them. I believe in miracles and I believe our seemly mundane every day existence is the miracle

[@n00bJesus]

As I was watching the 6 problems with warp drive vid, I was thinking what about entanglement, and if we could control a collection of entangled particles, etc. So I’m excited to watch!

[@quinnobi42]

I read a lot of science fiction. When I was younger, I naively believed that quantum entanglement truly could make FTL communications possible. But as I've learned more about quantum mechanics and how things actually happen, I became increasingly skeptical of the idea. The final nail in the coffin of FTL communication for me was learning that you can't observe particles at a distance. It's not like watching a ball roll on a table where you can see how it moves without affecting it. We have to measure particles using light, which (to use my earlier analogy) is like having to poke the ball in order to see which way it is moving. We can determine from the forces on your finger which way the ball was moving, but now that we've measured it, it's moving in an entirely different way.

[@Shirocco7]

Great description, thanks

[@subvind]

"you can't observe particles at a distance" - interesting... just thinking here: they say in order to move at the speed of light it's mass or information must = 0 ... ok that makes sense to me but what is the entropy of that thing moving at the speed of light then? What I am getting at here is maybe we don't need to "observe" what we already know because our methods of communication are based off patterns and algorithms (special relativity).

[@molybdaen11]

What if we use a very small finger and move ist very gentle and fast?

[@CosmicCraig]

I love what you have said here. I also have begun saying science fiction is really science future. I agree we need to understand the quantifiable data at hand, but that data. can sometimes change as our processes improve. Human ingenuity will always find a way to create the necessary tools for the universe

[@Vexas345]

@@molybdaen11 Doesn't matter. You're relying on the ball to impart some of its momentum onto you so you can feel it. It's not something you can avoid because it's a requirement to make the measurement, you need it to happen.

[@araptuga]

One reason I find so many Cool Worlds videos (including this one) so rewarding is that they conclude with a CONNECTION. A connection to human concerns, far afield from the original topic or even from science. I know that some will argue that "that's not science!" That this is opening the door to pseudoscience, to New Age woo-woo and so on. That science stops when pure logic and evidence stops, and should not keep walking into "speculation". And they're right that it's not science - but I believe wrong about the implications. I don't believe Prof. Kipping would claim to have shown any science-verified conclusions about these human concerns. These connections are not saying "science tells us the 'answer' to this ancient moral dilemma". Rather, the science is providing us with a new point from which to VIEW that dilemma. It's not an answer, but a tool. Perhaps from this new perspective we can reach our own conclusion with greater confidence, satisfaction, or even richness - but it remains OUR conclusion, not that of science.

[@aldejesus7195]

This is absolutely very well expressed! It’s also a science that seems without end

[@stephanieparker1250]

I loved this! You brilliantly cover a very heavy physics topic in such a way that makes it relatable and clear! I like that it’s a new idea for the channel yet also cleverly ties into previous videos. An idea for an upcoming video, maybe you can touch on how particles become entangled to begin with. It’s rarely covered in videos on other channels. Maybe bring it up when discussing the current record holders for distance between entangled pairs. 👍

[@aaronperelmuter8433]

It’s incredibly simple to produce entanglement between 2 particles, etc. One simply has to interact with it, that’s all. Literally ANY and all forms of interaction will produce entanglement. If a photon lands on your retina, that’s producing entanglement. Or if you feel warmth (kind of hard not to, if you’re alive. Lol) you’re absorbing/interacting with billions of photons per second, entangling said photons with whatever particle of your body absorbs them. That’s all there is to it.

[@stephanieparker1250]

@@aaronperelmuter8433 I read somewhere that the probability of an entangled pair resulting in true opposite measurement goes down the further they are apart. Is this something you have heard about? Thank you for the reply btw 🙌

[@aaronperelmuter8433]

@@stephanieparker1250 No probs, you’re very welcome. Ttbomk, there is no known correlation between distances of any size, small or large and the reliability of entanglement. Also, it’s purely an arbitrary choice as to whether one wants the spins opposing or matching. Come to think of it, quantum theory doesn’t really have any use of distance in an abstract form. Sure, interactions only take place when within a certain distance, e.g. strong force within about the diameter of a nucleus, etc, but when something is entangled with something else they can no longer be thought of as seperate objects. The very definition of entanglement is that all entangled objects are the object, the wave function is now describing all entangled objects, not a seperate wave function for each object. This is precisely why entanglement is so fast (instantaneous? I think not but how fast, I’ve no idea) as when an operation is performed on one of the objects, it (immediately) propagates the fact that an operation was performed to the rest of itself. It isn’t like if you touch your elbow and feel it immediately but touch your hand and it takes a few seconds to feel as it’s further away. In a manner of speaking, a person is one entangled system so when an update happens, no matter where it happens on your body, you feel it instantly. Entanglement can be thought of in a similar fashion. One can entangle any number of objects, but they will not be maximally entangled if there are more than 2 objects in the entangled system. Regarding what I wrote previously, I’ve a small correction; I don’t know that it’s possible to entangle a photon with a matter particle because I can’t think of any interaction which doesn’t result in the photon being absorbed by the matter particle (electron, neutron, etc. absorbs photon and gains energy of the photon but now said photon no longer actually exists. And since there is obviously no possible way to identify one photon from another, when the matter later emits a photon, losing energy, is it the same photon or actually a new one? I think it’s the latter. So, I don’t know any reason why dissimilar particles couldn’t be entangled, if they share the necessary quantum property, so a neutron should be able to be entangled with a proton, an electron and a neutrino, I think. I’m just gonna go out on a limb and say matter can only be entangled with matter and radiation with radiation. Also, reasonably sure their spins have to be of the same order, as in spin 1/2 or spin 1 but not mixed. Although, that’s actually the same as what I said a moment ago, matter with matter… Hope that’s of some help.

[@stephanieparker1250]

@@aaronperelmuter8433 it does help :) thanks!

[@jamesab-]

I feel stoned watching these

[@Test-nr3cd]

Maybe you are. 😊

[@KazuDiabolis]

i *am* stoned watching these

[@nizamieminov3648]

Stoned or stunned ? 🤔

[@ReynaSingh]

So much progress to be made, so much still left to know and wonder about. Keep up the great videos

[@frankiethebull8269]

"Open subspace frequencies" Something a lot of us heard in Sci Fi shows and movies.... they've had an idea about this kind of stuff in the 60s but lacked the technology to actually test for it or attempt creating it. It's not a question of "is it possible" the question is "how do we do it". Quantum particles (particles that can exist in two places at the same time) they seem to also have another characteristics, one being that it can "slip" into and out of some sort of void, a "subspace" that scientist can't fully understand or explain yet.

[@epimetheus8243]

We don't understand anything. We just measure stuff, get results and pray that our macrocosmos-based methodologies & tools are reliable in the world of quantum mechanics. At this point in time, all the "explanations" are just wild speculations, interpretations, philosophy, expressed by the limited human mind/ human imagination/ human language. When you say "particles can exist in two places at the same time" I assume you are refering to the "superposition-principle" which describes a mixed state of being. Being a particle and a wave at the same

[@mwansamatimba2750]

It's somehow related to the multiverse, because it does make sense that you cannot communicate FTL. It means one particle exists in another universe. Basically, the communication will be between two different universes. Thus it won't make sense to the other universe hence producing random results.

[@grimaffiliations3671]

If they gave out Emmys for KZbin videos your house would be full

[@charstevenson6817]

Yes, it is possible to use quantum entanglement to send information. This is known as "quantum teleportation," although it does not involve the actual physical transport of particles. In quantum teleportation, two entangled particles (typically photons) are used to transmit information from one location to another. The sender performs a measurement on the particle they wish to transmit, which destroys the original particle but also allows them to determine the state of the particle. They then send the information about the state of the particle to the receiver using classical communication methods, such as a phone call or internet connection. The receiver can then use this information to perform an operation on their entangled particle, effectively "recreating" the original particle with the same state as the one that was destroyed at the sender's location. The advantage of using quantum teleportation is that it allows for secure communication, since any attempt to eavesdrop on the transmission would disturb the entangled particles and be detectable. However, it is important to note that quantum teleportation alone cannot be used for faster-than-light communication, since the classical communication step is still limited by the speed of light.

[@WokeandProud]

This is utterly impossible too because of the uncertainty principle.

[@twelfthhausjones6753]

I'm sure this is the reason we haven't progressed too much with time travel. You mean I have to destroy myself to test it out? What about James. He never does shit around here anyway

[@ScottSuhr-l8m]

You seem to be describing the QKD BB-84 protocol. Despite the name, QKD is about agreeing on a key (mutually determining a key), NOT transmitting a key. You create a stream of pairs of entangled photons -- one is "read" by one user, the other by a second (and at least one of the particles has to be sent, speed of light to the other end of the channel). The classical channel (speed of light) is used to determine what measurement to make/which particles to measure. The HUGE problem with such approaches are that they are slow (bitrate - relative to conventional comms) and although they are secure because you can DETECT eavesdropping, they are EASY to "jam."

[@kathymoorehead7827]

@@twelfthhausjones6753😂

[@privatename7936]

I see: it's actually by checking the entangled particles' properties that they lose their entanglement. Hence, if you were to check whichever particle, the first checking of it will mean it spins a certain way, but then changing the spin won't work for the other particle. Also, just because you check that particular particle doesn't mean your friend in some other galaxy will too. That sucks.

[@bigphab7205]

I would think that if this were true then we would not be able to prove they were ever entangled in the first place.

[@semasiologistics]

Sure they can, since in the lab they know about both particles and can check the other one to see. It’s when they are separated by some given distance that it doesn’t work.

[@bigphab7205]

Well I seem to remember results of successful experiments being shared that were serveral miles apart. But I don't remember anything about the entanglement being broken during or as a result of the observation.

[@semasiologistics]

@@bigphab7205 That's awesome. I remember the record being broken too, and also that the entanglement wasn't broken.

[@bigphab7205]

The one where you said it breaks at distance.

[@ag6133]

We may not have found a FTL communication (yet), but we did find a truly random number generator, i would say!

[@nmarbletoe8210]

My half-elf is clapping with joy

[@molybdaen11]

I thought old defect ram chips would already do that.

[@2000bvz]

Fascinating and well explained! Thanks! The one thing that I don't understand is why we even think that Alice could measure the spin of the particle without altering it in some way that is unpredictable, regardless of what Bob did. I think that simply stating that Alice could not know whether the spin she is measuring is a result of her own measurement (which forced a random spin direction and broke the coupling) vs,. Bob's measurement (which forced a spin direction and broke the coupling) would be enough to prove that we could not use this method to transmit information. If I am misunderstanding this, wouldn't that imply that we could tell if a particle had had it's probability collapsed by someone else vs. us? I.e. if when Alice measures her particle she can tell whether the spin it shows was a product of HER actions vs. Bob's actions, then we actually HAVE transmitted some information. In that case, it would be trivial to send two particles, and have one be 1 and the other 0. By choosing which one to affect, Bob could send information back. But since it sounds like just the act of Alice measuring her particle will force it to choose a non-determinate state means that no such information transfer is possible. And that fact alone would eliminate any chance of using this as an FTL communication method no matter how many tricks we try. And perhaps that is exactly what the video explained, but I just didn't fully grasp it.

[@KurtKobain01]

Wrong wrong wrong! Spin correlation can be influenced and predicted or Quantum Computers wouldn't function. Quantum Computers use entangled Qubits to do computation. Qubits can be atoms, electrons, photons, trapped ions (Positively Charged Calcium atoms, superconducting, etc... If spin state correlation unpredictable and there was only a 50/50 chance of guessing that correlated state then Quantum Mechanics wouldn't be the most successful theory, quantum systems and their interactions would be random and all matter in the universe would cease to function and break down due to a lack of structure and coherence. I suggest that you build a foundation of factual scientific knowledge by going to school, rather than allowing yourself to be mislead by people like this fella on here. You're just regurgitating nonsense.

[@illbeV.]

Could anyone else who's not a complete dick like this kurtKobain dude answer the OP's question? I'm interested, too

[@pablocopello3592]

This is the best "not expert" exposition of this topic I found in this network. So I will add a little more. 1.- There is nothing FTL here; what we have are cause-effects that do not follow the space-time structure (like all cause-effects in classical physics). That is: do not try to maintain the idea that space-time is the structure of all cause-effects. There are not either "instantaneous" effects, because simultaneity is not universal and is a space-time related concept, while quantum correlations are more fundamental than space-time (ST is just an "emergent" phenomena (emerging from quantum correlations) under certain conditions (that includes our most immediately experienced domain of reality)). 2.- Uni-dimensional and uni-directional time is a way to avoid causal-loops. Avoid causal-loops is a way to avoid contradictions in our models (theories) (paradoxes for the modeled reality). But, we do not need to avoid causal-loops, (as we do not need to avoid loops of proofs in a mathematical theory), to avoid contradictions. Causal loops seem anti-intuitive because it seems to "collide" with "free-will", but QM and its follow-on (when we could model how space-time emerges) are just models, whose target is not to find the "final truth", there is NO final theory and at each level we have to use the concepts that better adapt to the domain of reality we are modeling, and know that the models should not be extrapolated outside their domain of application (like to say if we have or not free-will).

[@jade59230]

Ok, is FTL communication feasible or not?

[@pablocopello3592]

@@jade59230 the point here is that fot something to have a speed, it has to move thru space-time: have a path (or paths) thru space-time, but the effects consequence of quantum correlations (entanglements) do not travel/move/propagate thru st: there is no possible barrier or even modification of metric or topology of space time that could diminish or alter in any way that effect, because that effect is outside space-time, and so it has no speed, and so it cannot be said that it is ftl. Ask if that effect can be ftl, would be as to ask if Mondays are heavier than the Earth.

[@StringfellowHawke197]

You can definitely send messages instantly using entanglement. Just have one entangled pair represent a pre-determined message. For each pre-determined message, you will need another entangled pair. Once you choose a state for one of the pair, the other paired particle will react and trigger the pre-determined message.

[@MichaelHarto]

Yes that's what i think too

[@manofsteel8728]

but the whole idea is you don't know what way the particles will be spinning so there is no way to comunitcate even if the particles are entagled.

[@MichaelHarto]

@@manofsteel8728 it doesn't matter which way it spins. As long as the superposition collapses then we can confirm the predetermined message.

[@SaintMorselGrand]

@@MichaelHarto i just commented on something similar

[@StringfellowHawke197]

@@manofsteel8728 I just told you how to communicate even if you don't know which way that they are entangled.

[@brothermine2292]

Special Relativity says everything travels through 4-dimensional Minkowski spacetime at speed c. Technically, the equation is: the square of speed through 3-dimensional space plus the square of the rate of aging equals c squared. It has some well-known corollaries, such as "the faster something travels through 3d space, the slower it ages" and "light doesn't age." It implies that something traveling through 3d space faster than c would age at an imaginary rate (the square root of a negative number). I don't know whether it's physically possible for something to age at an imaginary rate, but its impossibility would need to be proved before one may conclude that nothing can travel through 3d space faster than c. Also, let's not forget about the possibility of wormholes.

[@Dragrath1]

Wormholes might not allow information to be able to travel faster than light as there is some work which suggests there is a delay between relative travel through a wormhole i.e. while to an observer traveling through a wormhole it appears instant there is a delay in when they are able to emerge from wormholes(Edit specifically they show this delay will always be longer than it would take for information to travel causally at the speed of light). Of course this was for wormholes built off of the quantum vacuum.

[@richardsrichards2984]

yes a little mostly no...But there is no travelling through anything for quantum entanglement...assuming you can measure and influence spins without breaking the entanglement you have faster than light communication...and pliz still remember we dont have a quantum theory for gravity...... .plus failing into a blackhole already breaks your so precious causality rule bz its the same reason light cant escape...

[@OldManShoutsAtClouds]

@@richardsrichards2984 right? Says it's not possible because it breaks our model, then immediately gives examples of real world phenomenon that breaks our models.

[@brothermine2292]

@@richardsrichards2984 : 1. You claim that entanglement doesn't involve travel through something, but you don't know that. For example, the "ER = EPR" paper by Susskind & Maldacena hypothesizes entanglement involves a wormhole. 2. Your assumption that spin can be "measured and influenced" without breaking the entanglement is inconsistent with quantum theory, which is clearly stated in the video. 3. In what way do black holes violate causality?

[@Dragrath1]

@@brothermine2292 Yeah the question of how to interpret entanglement is thus far unresolved but ER=EPR looks to be one of the most promising results especially with recent work showing it can be reached purely from the context of General Relativity alone without needing supersymmetry or other quantum models of gravity. How or what this means is unresolved but probably the most interesting insight at least to me is through looking at the implications of the No big crunch theorem which proved through contradiction that no nontrivial flat or open universe that is initially expanding can ever stop expanding i.e. for the Einstein field equations to exhibit logical internal consistency the total volume in any slice of time must always be larger than the preceding slice of time's volume forever. This comes about in modeling because contrary to what has been often assumed for simplicity the off diagonal terms in the metric tensor can never cancel out. The implication of this is that the metric at any place in spacetime is nonlocally constrained but as causality holds this implies that there must exist a significant nonzero contribution to the metric tensor, i.e. the only way for the Einstein field equations to be logically internally consistent is if there is a nonzero ground state for every gravitational interaction i.e. gravity must be quantized or else the metric fails to be logically self consistent for all possible initial conditions. Taking the quantum limiting case of the energy stress tensor thus implies each term of the metric tensor at the smallest scale must have a unique valued nonzero contribution from every possible or impossible interaction pair i.e. the metric tensor can be viewed as a sum of all entangled states within a Universe letting us arrive at ER=EPR based on the need to avoid logical paradoxes. It also appears based on the limit analysis that the constrained sum of nonlocal terms have properties consistent with dark energy(cumulative off diagonal elements traditionally assumed to be negligible to simplify the math) or perhaps even dark matter as the sum of additional nonlocal diagonal elements look suspiciously similar to the terms from MOND(and if true would mean that MOND is automatically built into the full unconstrained Einstein field equations) and the laws of thermodynamics and the arrow of time emerge trivially from the conservation of information via Noether's theorem. The downside is the cosmological principal can be shown to be fundamentally invalid for any and all possible solutions to the Einstein field equations as in there is no logically self consistent way which it can ever hold without either breaking causality or resulting in an inescapable logical self contradiction analogous to the Liar or grandfather paradox. Frankly in hindsight it seems blatantly obvious that the cosmological principal must be wrong after all the assumption means you are throwing away information which is forbidden by the conservation of information.

[@frankroquemore4946]

My question has always been “how exactly do we know that the particle state is genuinely in a superposition and not just in a position unknown?” I’ve heard explanations of this and it’s never quite clicked with me. What I’ve heard feels like circular reasoning, so I’d love a video detailing this concept for a layperson like me

[@nick_8564]

I think John Stewart Bell proved that there is no hidden variable with his Bell's theorem. There are some good youtube videos about Bell's theorem but I would like to see Cool Worlds making a video about this too.

[@pyropulseIXXI]

First off, there are no particles; we are dealing with waves of an underlying field. What is mass is oscillations of a field; higher mass equals higher oscillations; this is one model; the other is higgs coupling via electron spin flipping. There are still masses that we cannot account for via the higgs mechanism

[@pyropulseIXXI]

Superposition is just that if both f(x) and f(y) are solutions to the Schrodinger equation, then the sum of f(x) + f(y) is also a solution to the Schrodinger equation This has nothing to do with whether we know the position or not; in fact, the x and y are positions, so we get two waves that are a solution, and this means that the sum of these two waves is also a solution

[@jaybingham3711]

Unknown is referred to in physics as "hidden variables." Interestingly there's a way to explore that as a possibility. Whether it ought to remain on the table as a consideration. Unfortunately, it's done in a manner that isn't intuitive to a layperson. You're far from being the only person to struggle with precisely how we (well, John Bell) decisively determined hidden variables can't be in play. Here's a good treatment of what's what: kzbin.info/www/bejne/nGiVqJt9hphkjck Tough it still may take several rewatches and some extra reading before overcoming any sense of circular reasoning. It absolutely isn't. It just involves several uncommon areas that most aren't up to speed on. Not simple. But also not impenetrable for a layperson. Good luck.

[@prototropo]

At 2:50, my heart dropped as the video visited that transformative scene from "Arrival." No other film or book raises the alarm--or potential beauty--of challenging, or crossing, the bounds of causality. Just considering that possibility brings me chills, and in the movie--tears.

[@sy14]

Such a thought-provoking video. Thank you. Keep up the great work.

[@shotdoctor5869]

You could have 2 pairs of entangled pairs (4 total particles). If bob wants to say “yes, it’s safe”, he untangles the first pair. If he wants to say “no don’t follow” he untangles the 2nd pair. You’ll need a detector which says if a particle has untangled or not.

[@ArtsFantasy]

I was thinking of a similar solution. Basically a morse code signal where a "tone" = either up or down spin. It does not matter, what matters is that the state has changed. Lack of change means 0. Am i missing something here?

[@AdapG]

A detector would be essentially measuring it which would untangle it

[@nickmonks9563]

You can't measure if a particle is entangled. You can measure it's other properties (like spin), but once you do, you have no idea if you collapsed the wave function or if the person on the other end did. If I collapse "yes" but Alice measures and collapses "no", neither of us know that both entangled pairs have already been measured. We have no information out of the system.

[@KazukoKodo]

@@nickmonks9563 It feels like the state of being entangled should be measurable, because otherwise, how could they measure the speed of "spooky action"? Just look at this statement for an example: "The experiment involves performing a measurement on one photon and then timing how long it takes for the other photon to be influenced." They measured the other photon's entangled state, right? Unfortunately, what they really measured was a stream of photons, and watched for the moment that stream of photons changed their behaviour. It would take a LOT of entangled particles, continuously measured, in order to get a single bit of information when Bob finally decides to send his signal. But, in theory, with enough particles and a perfect setup, maybe it's possible? I'm probably missing something here, so I hope someone will enlighten me.

[@nickmonks9563]

@@KazukoKodo I think I see where you're going with that, but I'll let an actual expert speak to it. I *believe* they can only measure this phenomena in particles they themselves have entangled. Further, I believe the effect is instantaneous upon measurement regardless of location. It's weird, right, because both particles *are* in a superposition until measured...that's just how the quantum realm works...but from our perspective it seems tricky, as if once entangled they've already decided their state - but they haven't. They are, indeed, resolving their state at the same "time", or at least only at the point of measurement (?) It definitely hurts my brain. Reminds me of learning about electricity, and how no macro level analogy perfect explains electricity (water through pipes, etc...) The observations had to stand on their own, no matter how weird they may seem.

[@darthevol5734]

Thank you for your videos. You have a way to engage and make my brain hurt in the first 9/10ths of your videos, then engage and make my heart hurt (in a good way) the last 10%.

[@LastEmpireOfMusic]

i wouldnt call it entanglement anymore if x1 messurement on one side and y2 messurement on the other breaks the pattern. the problem seems to be with the messurement equipment that hasnt been invented to be precise enough

[@jlwilder8436]

Beautifully well done, this one. (A lot of them, but still...) And the way you ended this one in particular was really poignant and lovely. Also, thank you for all your reference points left "down below" for us. A big part of what make your videos so special is: A. Your guided, musical narration, and B. The beautiful music you & your team layer into them. But putting the music, movie and other references down below is very cool and really sets your channel apart. 🙂

[@fanfam]

Yes indeed. Well spoken.

[@bobbyp9786]

If we do figure out a collapsed state communication, I like the idea of using a worm hole to place many of the entangled particles somewhere out in the distant universe, like communication relays. Now we need to create small worm holes in near by space.

[@jaywulf]

If you can create wormholes, you don't need FTL. You can use radio via the holes.

[@bobbyp9786]

Radio signals can be used only when the worm holes are open and once relays are placed and holes are closed, distance is irrelevant . They could also be used as long range sensors.

[@bobo-cc1xw]

So to make ftl comms useful we just need a method of ftl? So we don't need picket ships

[@EddieA907]

Amazingly explained. Thank you for all your efforts I always look forward to your new content.

[@JohnB-sp3de]

As someone who has a background in Physics, I always went along with the accepted point that the randomness within a quantum entangled system prevents FTL communications. I recently read a book 'Cracking the Cosmic Code' which actually shows that the randomness is not a restriction at all. It now opens up the distinct possibilities of FTL communications.

[@mute888]

intrsting! could you please tell more about the book, like the author or a link. I can not find any book like that.

[@triklop_8708]

So one idea I had about this is Bob kinda achieving a statistical shift for Alice. Let's say Bob has 1000 sets of 100 particles. Bob wants to communicate a 1. Bob measures, until he gets a positive amount of 1s over 0s in his set of 100 and leaves the rest open. Then he continues with the next one. Alice would get a higher amount of 1s than 0s plus a random amount until 100. That would achieve a statistical shift towards the 1s, that gets more significant the more you measure. You would basically communicate, when you are more likely to stop measuring.

[@Blazagg]

On average you'll get 50% 1s and 50% 0s in each set. Even if Bob is able to observe 30 1s and 20s in a set (that's already rather unlikely), Alice has to observe all the particles which collapses their state. In the end your 1000 sets will just spit out a 1 with 50% chance and 0 with 50% chance. You're just postponing the random observation from a particle to a set of particles.

[@spacewarp607]

what if you just get 1 in any position is a 2 is b and so on

[@sk-sm9sh]

@@spacewarp607 all these searches for FTS comms basically fall flat in same principle like infinite motion machines. Smarter person may come up with a more complicated scheme that may get take more effort to debunk. But eventually it goes down to same thing. It's impossible just like infinite motion machines are impossible.

[@Trepur349]

When you think about it fom the perspective of Alice, if she observes the particles in the exact same order as Bob she'll be able to tell exactly when in each the set Bob stopped his observations (both in cases he wanted a 0 and in cases he wanted a 1) but she will end with equal numbers of 0s and 1s, and so will have no idea if he intended to stop at the 1s or stop at the 0s

[@The_Primary_Axiom]

I want to know how the hell they’re influencing each other at those distances. How does one know the other is up. Lol

[@zx3215]

There are two identical socks. When you put one of them on your right foot, the other instantaneously turns into "left" sock. This effect does not depend on the distance between the socks. The information about that other sock turning into the "left" one can cross the entire universe in an instant. Woo-hoo! Quantum teleportation at home!

[@jonathanrobertson3406]

This is such an excellent video. I asked this exact question of my Physics Professor twenty some years ago and he essentially gave the exact same answer in a nutshell; but this video goes into way, way more detail and also explores possibilities I hadn't even thought of. Again, VERY well done. PS - Concerning coin tosses, if ever asked to pick heads or tails, always pick heads. There has actually been studies done that, at least with American quarters, you have a very, very slight advantage choosing heads. Not sure why, but my guess is that if you were to evenly split a quarter right down the middle into two separate discs, the weight of one side would be slightly different than the other based on the physical printing on the surface. But apparently, it is a real thing.

[@dananorth895]

Correct but the difference is still infinitely smaller then the noise. Think signal (event) to noise ( all possibilities) level.

[@jonathanrobertson3406]

@@dananorth895 Interesting. Thanks.

[@Pencil0fDoom]

Citation?

[@Scott_Raynor]

@@dananorth895 ?? Explain

[@Rohitmanotra664]

I am fan of you by just watching only one video. Thank you for this video.

[@leesweets4110]

I have another question though. When you send an entangled particle off to the xurdu galaxy, presumably your spaceship would get there by traveling at high speed, say near the speed of light. Thus relativistic effects must be considered. Even at slow speed, say to Mars, there are relative inertial frames. One particle would experience time differently than the other. So the question I have is this: Do the particles effect one another in absolute time, or in terms of the particles own age? That is to say, is the effect of collapse still instantaneous for particles that have experienced the flow of time at different rates? Im wondering if the effect of relativity will nullify the benefit of instantaneous transmission, even if effective communication could be established.

[@birdsintheburbs7414]

Great question. I'd like to know as well!

[@Spugler2]

Entangled particles don’t affect each other at all.

[@marcus3d]

Ponkey77 is right. This video is wrong. Entangled particles aren't affecting each other. Check some real physicist, like SH, for a proper explanation.

[@leesweets4110]

Youre deliberately trying to misdirect the point of the conversation over a semantics issue.

[@Spugler2]

@@leesweets4110 No, I’m not. Entangled particles literally do not affect each other.

[@moriahgamesdev]

These Quantum Myst puzzles are really tricky. What Alice needs is a device that can measure the time between two particle changes without actually looking at them. Then it's just Morse code. She needs a sixth sense machine.

[@Hansulf]

Yeah, but the moment you measure the particle, the same moment you interact with It, It colapses and there is no way to know if It was already commited or not.

[@gerrycanyerryyerry9641]

Quantum is a fantasy word, like SEGA's blast processing. Nothing can travel faster than the speed of light. I believe Einstein was very clear about this.

[@unicorn_tamer]

@@Hansulf But what if we could measure it without interacting with it?

[@mickyr171]

@@Hansulf Had the same idea and came to the same conclusion a few years ago, you could use the OPs idea to send a message but there would be no way to receive it as the act of trying to read it would collapse the states if they hadn't been already

[@mickyr171]

@@unicorn_tamer Just like the double slit experiment, you have to interact with it to know what its doing

[@6Planet]

So it seems like the only remote possibility of FTL communication with entangled particles would be if we discover a way to tell if a particle is still entangled to another particle or not without actually measuring it and causing it to collapse the wave function. (Maybe impossible?) Then if we could run this check on an entire array of particles at a high enough "frame rate" to know WHEN a wave function on any one of them collapsed, it would be possible to send data through the timing of when the person on the other end made the measurement, similar to morse code. I guess this was the idea behind sending the particles through the double slit experiment in this video. Maybe some method that would actually work will show up.

[@Wolf-zk8ey]

I feel like I thought of something similar... to forget about whether the entangled particle spins up or down, and focus on the timing in which it is measured in relation to the next measurement. You could create a rule based on the time between measurements to understand what someone is trying to say. You may not be able to control which side of the wave function you end up on, but you can control WHEN you observe it. I think of it as "Quantum Morse Code".

[@noelstarchild]

Two years later and I stumble across this Cool Worlds upload, although in that time it is just under half way to the next star over...wow! For me? Back to the Vogon poetry book. Really interesting, thanks all.

[@victornoya9148]

You are a true professor, my friend. To take such a complex subject and make it so easy to understand is a truly amazing. I love your videos. :D

[@cemberendsen4297]

This was a very inspiring video! keep up the good work!

[@SebsWorld]

What about using entaglement to simply measure the 1 way sleed of light? For the calculation, entanglement could simply provide a accurate timing trigger.

[@dominicmillerca]

The idea is interesting but I don't think it could work because there's no way to know if the entangle particles was read on one side or the other. If it was possible to use the entangle particles as a trigger, it would be possible to use them for FTL. From my understanding, the reading of far away entangled particles doesn't need to be synchronized.

[@SebsWorld]

@@dominicmillerca well id imagine that the outcome of the spin in a single speed light measurment does not matter as long as the trigger produces a change in state of entanglement to be observed. The results of the trigger carrys no information other than "something happened", i.e the change in state is only triggered to calculate a measurmen.

[@jc33353]

@@SebsWorld This was addressed in the video. The only way to detect a change in state is to repeatedly measure at the receiver looking for differences, but the first time either particle is measured, they are no longer entangled and state changes are no longer meaningful.

[@MCsCreations]

That's what they use to detect gravitational waves.

[@CoolWorldsLab]

@@dominicmillerca yup there’s no observable trigger, Alice has no idea whether Bob has observed or not

[@KevinDC5]

i must say, i just subbed a couple months ago, but this is a GEM of an episode bro! good work!

[@afellowman6760]

In regards to the 3rd type of QEC, is it possible or is there a proposed method to measure both the x and y axes simultaneously?

[@John_Fx]

Simultaneous isn’t a real thing.

[@bobifg320]

Alice measures on diagonal

[@Kilen_BE]

Until the day we find a way to make our own version of elementary particules and give them some properties aside their natural abilities to interact with one an other across vaste distances instantaneously. That would be the only way to use their properties to communicate in some way. But how to do that, that’s an other serious challenge, probably impossible, but who knows maybe there is a backdoor to that problem we haven’t seen yet. That was interesting, always a pleasure to watch your videos 🙂

[@dwightc3080]

There has to be a universal standard that more advanced civilizations use to communicate. A sort of Rosetta Stone for long-distance communication.

[@knuthamsun6106]

@dwight- 1. no there doesn’t. 2. rosetta stone would not function as an analogy for some FTL communication any better than a salamander

[@bassem500]

In all versions of quantum communication attempts you mentioned I have not seen one which takes a similar approach to the quantum computing approach. Quantum computing is limited in what it can compute, because it uses convoluted methods to arrive at results. I still believe that there are convoluted structures of entangled quanta, which allow for FTL communication... It just needs an engineering approach. I'll try and tackle this one when I do my doctorate. 😉

[@shanehudson5438]

Good luck mate

[@varany3376]

We are rooting for you. Hope you'll get to pursue your dreams.

[@Shep01]

As a layman. If you can entangle something which we confirmed already then we definitely will work out how to use it for FTL. Communication. It might start out simple as a telegraph before working it up to computers talking. But here's a thought if you established a real time link. But time is passing differently I assume the communications couldn't speed up or slow down at their respective locations

[@varany3376]

@@Shep01 The kicker is, there is no new information being transmitted. You simply also have information about the other part of the system, because it's complementary in a way (if my coin says heads, I know you got tails). We would have to meet again and make another entanglement then travel very far from each other again to "communicate" further, but this is not FTL at any point. Once you look to see if you get heads or tails, the two systems untangle go through decoherence.

[@fearlessIFI]

I am Quantum 😂 Pleaseee helppp meee. Bassem....I fucking sent myself to be birth in this day and age...get me off this planet of aliens haha...No one is probing me anytime soon

[@florincosma]

Can we use time as part of communication? I am no physisist but... if X changes the particle and Y sees a change, this could be part of the message in the first second, let's say it could be understood as „1”. In the 2nd second we change nothing and that would be a „0”. The 3rd second we change the particle and that would mean a „1”, etc. In seconds 4 and 5 we change nothing and those would be „0”, etc.

[@garette8672]

if we could tell if a particle’s wave function had collapsed than we could simply say that an unobservered particle is 0 and an observed particle is 1. since we cannot tell if the wave function has collapsed, we can’t tell that there was a delay in observation.

[@lukemitchell1975]

i like this guy, he explains science in an amazing way 🙂

[@maalekar]

A question. I read on a recent article that they had tested entanglement 24km apart and it held. That said your article states the function of making the connection is local. So are they physically transporting already entangled particles apart to achieve that? I realize then that due to lack of locality we can't get a stream of them to create FTL communications, but, it does seem that it's impossible under current understanding. Let's play a game... what if we can localize a wormhole link of sorts between them? Of course, then the comms wouldn't need to be quantum based either ;)

[@kingston5710]

If you can get a worm hole we can just use a normal piece of paper write down what we want and pass it through 😂

[@dendricalabro5058]

hello, thx again for the usual beautiful video, I really love this channel. I was looking to the carton at min 13:57 and what you said makes totally sense. But I m wondering if there is a way to deal with a limited number of particles and introduce a time break between measurements (as the break we introduce during morse code). For example: bob make a tot of observations until he hits a spin up. Alice sees that the last particle is down. After a while bob makes another measurement until he gets spin down, alice see the spin up. If we introduce a time break during multiple measurements, we should be able to send a message. But I m sure that also in this case the devil is in the details.

[@iketagg1965]

this is almost exactly what I was thinking. But you could simplify it even more by just using precise timing of the observation. Who cares if it is an up or a down spin, its a beep, time the beeps and you have a sort of binary morse code. Of course this is all dependant on whether Alice is able to instantly detect if a particles spin has been resolved. Alternatively for very basic information you could just separate the particles into individual cells, with a matching cell at the receiving end. Each cell represents one specific meaning like "all is well". one side just needs to observe one particle in that cell and the other side will get the message. You can't send poetry but you could have a few thousand premade messages.

[@emilymader5206]

I've been thinking about this for longer than I care to admit. The problem is alice wouldn't be able to know which is the last particle because lets say Alice reads 1:down 2:up. Does she assume Bob stopped at 1 because he wanted her to read 'down'(and got his desired state first try) or that Bob stopped at 2 because he wanted her to read 'up'(got desired state second try)?

[@tankfire20]

How will Alice know when Bob stopped? All she will see is random spins.

[@pedroascencio_]

If we can choose the axis in which the quantum wave collapses, regardless of orientation, we could express it as such: X = 1 Y = 0 That way the receiver will always be able to decipher the message.

[@pedroascencio_]

Alternatively, even if the wavefuction doesn’t collapse in the desired state. Couldn’t a Hadamard Gate set it back to Superposition until you get a new state?

[@MoOrion]

I've wondered if Quantum entanglement might indicate the existence of a Subspace... or Hyperspace... to use Scifi terms, that me may one day learn to manipulate for communication or travel.

[@molybdaen11]

Or it might show that distance is an illusion.

[@Vartazian360]

I like the last analogy with the shoe boxes. Perfectly fits and explains why no communication could occur. When you open the box on your end and see it is the left shoe you know that the other box contains the right shoe. But the other person does not know that until he opens his box. No new information was generated instantly. Very bizarre thing entanglement is.

[@HussamHadi]

Nice video and I still have a question about it. How do we as local observer know if we have collapsed the particle or the remote observer has done that? E.g. if Bob has reached destination and collapsed theirs or not, as local observer we don’t know that yet, so the moment we check our particle, how can we be sure that Bob has collapsed it and not us?

[@kafkaten]

I'm glad you asked - I had the very same question!

[@cassiel1970]

That’s the problem, you have no way of knowing do you. If you’re waiting for a communication, how do you know when you’ve got one? You can’t be sure when you check your particle which of the two people collapsed the wave function first. I thought a lot about this but always came to a dead end. What if you had preset communication times? Alice’s FTL device could be scheduled to check the spin value 1 second after Bob ‘sends’ the spin state from his end. As long as both devices are time synced allowing for time dilation this should work. Problem is, so what? You’re still going to get a random value. Then I thought what if you had to generate a set sequence of states using multiple particles in order to record a result? So after your scheduled coms time you check for 3 ups, actually meaning up, and 3 downs meaning down. So you get 3 ups, great! But what if Bob was actually trying to send 3 downs but just randomly got 3 ups first? It just doesn’t seem doable. So the only way I could think of to overcome the ‘who collapsed the wave function first’ problem is to use time based message scheduling, but even once you’re past that there doesn’t seem to be any way that you can structure a message to be 100% certain of what is being sent. I did consider that maybe you could improve your chances of sending a correct message by using a longer chain of the same value, ie. you need 10 ups to designate up instead of 3. But then you’d still have exactly the same %age chance of generating 10 downs first, so your message is going to be just as garbled. If we are unable to influence the outcome of the state change (spin up / down), the problem is always going to be how can we structure a sequence of random outcomes into a coherent message, without ANY additional form of communication? I guess that’s one for mathematicians, but if the wave function collapse is truly random then I don’t see how it’s doable.

[@mjblcmichael]

@@cassiel1970 You're absolutely right. Darn. I guess it would be like communicating with a random number generator.l

[@firewallpriest]

For everyone feel depressed about unplausability of FTL travel or communication, this all feels so after comparing to human lifetime. But we are capable to change our species to enlarge this scale up to the point time required are nothing in compare to future post-humans. I don't know how would you feel about it, it gives me relief and hope.

[@dsoprano13]

Great video. I also thought of the approach to just detect if the particle was observed or not since we don't really need to force a specific spin. But apparently that idea is shot down. At this point the only answer seems to be able to force the spin in a desired direction. Not sure if that will ever be possible.

[@nw4042]

That's what I was thinking. Not sure why that gets shot down either. Folks smarter than you or I haven't figured out yet though.

[@DavidByrden1]

The quantum theory explains all this. You can't force a spin and you can't see if a particle has been observed or not. Unfortunately this video was made by somebody who does not grasp the quantum theory. Here's a life tip : KZbin is not a college. Idiots are free to post nonsense here.

[@stickyfacade3388]

Yeah I was wondering how you would even know if the person communicating had observed the particle without having to observe your own particle 🤔

[@Erikaaaaaaaaaaaaa]

@@DavidByrden1I don't think you understand the video, Dave

[@DavidByrden1]

@@Erikaaaaaaaaaaaaa Well, I am absolutely sure that the video maker doesn't understand QM. I listed his mistakes in another comment. Given that the video is full of mistakes, there would be no point in my "understanding" it. But, feel free to tell me where you think I went wrong? I'm sure I can teach you something.

[@DoctorParadoxExtreme]

One question here : Is there a way to know whether a particle is entangled anymore or not? If yes, then we can communicate by breaking and not breaking the entanglement by bob and then by being observed by alan at a predetermined time for predetermined particles. I hope someone understand what I'm proposing and answers my previous question.

[@JayCyano]

In the solutions proposed in this video the awnser is no.

[@DoctorParadoxExtreme]

I'm saying.. Not to observe the state of entanglement, just whether it is entangled or not.

[@LEDewey_MD]

Good explanation of how quantum entanglement works (and acknowledging how many have thought about using it for FTL communication). Another mind blowing phenomenon of quantum physics is the "delayed-choice quantum eraser" experiment. (Explained eloquently in Brian Greene's "The Fabric of the Cosmos".) This would keep many awake at night as they tried to wrap their heads around it! :)

[@stephenmarshall5529]

What I love about this is that, if the purpose of communication is to cause something to happen (launch the ships, the planet is habitable!), the speed of causality remains unviolated! just because the particles are entangled doesn't mean that action can be forced in any less time than it would take for a light signal to cross interstellar distances.