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Quantum Entanglement Survives, Even Across an Event Horizon
StartsWithABang writes: One of the more puzzling phenomena in our quantum Universe is that of entanglement: two particles remain in mutually indeterminate states until one is measured, and then the other — even if it's across the Universe — is immediately known. In theory, this should be true even if one member of the pair falls into a black hole, although it's impossible to measure that. However, we can (and have) measured that for the laboratory analogue of black holes, known as "dumb holes," and the entanglement survives!
This should come as a surprise to exactly no one. Anyone who can apply logic can tell you that the physical universe is a layer above the non-physical energy (matter is merely 'bound energy') that is the fundamental substance of existence. Quantum particles are known to "flicker in and out of physical reality". That has been directly observed. So where do you think that energy goes when it's no longer *physically* present? Just disappears into nothingness, the one state that's simply not possible whatsoever? Of course it's still there, and of course the rules that apply to that non-physical energy still apply even when you can't physically access it. Energy is information, matter is merely a storage medium. The information is always extant, even if it's not currently represented on any physical storage medium.
A simple way to understand this is to visualize the universe as being made of numbers. The positive numbers can be represented by matter (regardless of polarity, so yes, anti-matter is positive numbers) and negative numbers cannot be represented physically, but are nonetheless just as 'real'.
Anyone who argues otherwise, yet agrees that 2 minus 5 equals negative 3, should be required to demonstrate physical proof that 2 minus 5 equals negative 3 before being allowed to speak further on the subject... ;)
- For everything above quantum, the maximum speed is the speed of light.
- This dictates cause and effect, and therefore time.
- If we send out a steady stream of entangled particles, and sometimes change and sometimes don't (at the one end), and measure at the other (this is how I imagine how a bitstream would work using quantum entanglement, correct me if I'm wrong), we can send information quicker than the speed of light.
- Therefore the information goes back in time.
Or something?
Religion is what happens when nature strikes and groupthink goes wrong.
Ouch, A downvote! Let's be fair though. Carson and Trump are clearly quantumly entangled because once a voter realizes one of them is full of sh*t they immediately know the other one is as well. It's science!
Bob finally has an excuse to throw that cheating bitch, Alice into a black hole: science!
Anons need not reply. Questions end with a question mark.
In the many-worlds interpretation of QM, also called "QM without collapse", becoming more and more mainstream, this is a straightforward consequence of entanglement. When you measure the spin or polarization of your entangled particle, you become entangled with it, so in a sense all you're doing is discovering which "universe" you're in. And of course that universe is correlated with the corresponding other particle, no matter where it is now.
Unless nasa has gotten some really interesting data from SETI im pretty sure its from outside of the light cone of the experiment, not an actual event horizon of the black hole.
Not that the actual paper or press release is linked at this time (who reads those?) but there have been experiments lately that close loopholes in bells theorm and show that the details are truly random until measured yet correlated upon measurement. This includes determining the experiment details randomly from outside the light cone of the experiment using advances in optical measurement of single photons and random number generation.
link to a related article
What I think is the really important thing in the original paper is that information actually seems to be lost in the black hole. There is an enormous amount of theoretical musing about how to prevent information loss at event horizons (remember the black hole firewall?); this, if taken seriously, could have implications in quite a number of areas in theoretical physics.
All science is based on statistics, you anonymous moron. There is always uncertainty in experiments and measurements because one can never be certain about anything - even the instruments used to measure observations have inherent uncertainties. Is the ruler you're using precise down to the atomic level? No! Can you be certain your instruments are perfectly calibrated?!?!? No!
This higgs was discovered with 6 sigma accuracy, which is more certain than the precision of manufacturing of most things you can purchase. It's the standard for declaring experimental certainty. If you're 99.9999998 % (which is what six sigma means) certain , there is literally a 0.0000002 % chance that the results were wrong. No one is going to bother to test beyond that, because the possibility of an error is so small it may as well be non-existent.
A billionaire businessman and a successful brain surgeon have nothing on you, right?
Get back to me when you match their success.
This particular thing about event horizons always bugs me (i am no scientist at all): If the stuff falling in never enters from an outside perspective, shouldn't black holes look like Katamari balls and be quite visible?
Well, I'm pretty sure I know what the pyramids were for. Also 0% ob the people I've stabbed with murderous intent have survived so I'm winning there as well :)
Quantum entanglement requires a pair, AC. But thanks for playing!
Imperial Entanglements? Can we at least avoid those
So tachyons or neutrinos are "below quantum"? If so, what does it mean to be below quantum?
There is no such thing as "below quantum". Tachyons don't exist (or at least we have zero experimental evidence that they do) and neutrinos are most decidedly quantum in nature since they are extremely well described by quantum field theory.
Think about how vision actually works; photons emitted from a light source bounce off of an object and enter your eye. Your eye detects the photons, and your brain constructs an image of them based on their wavelength and direction of arrival.
You can't see a black hole because its gravitational field is strong enough that even light can't escape. Since no photons are bouncing off, there's literally no way that your eye can perceive it.
Karma: Terrifying (mostly affected by atrocities you've committed)
For everything above quantum, the maximum speed is the speed of light.
No, for everything which can transmit information the fastest speed is the speed of light. If we find anything which can transmit information faster than light then time travel is immediately possible. You will know if this ever happens because the physicist who discovers it will get extremely rich winning lotteries.
If we send out a steady stream of entangled particles...we can send information quicker than the speed of light.
No - as witnessed by the the fact that we still rely on government grants to fund us and not winning the lottery. Quantum entanglement does not allow any information to be sent. It is like shining a very powerful laser pointer on the surface of the moon. The person on earth doing this could move the laser fast enough that it would appear that the bright dot on the moon's surface moved faster than light BUT the information flow is from the person on the earth to the moon and NOT from one point on the moon to another so there is no problem with relativity.
Quantum entanglement is the same sort of thing. You cannot use it to transmit any information faster than light. However unlike the laser on the moon it is very hard to come up with a believable explanation for the phenomenon which does not involve faster than light communication even if it will be impossible to use to transmit information.
neutrinos merely go faster than light when that light goes through a non-vacuum medium, like beta radiation that makes a nuclear reactor glow blue in the swimming pool.
The blue glow is Cherenkov radiation which is caused by electrons from beta decay of fission products travelling through the water faster than the speed of light in water. However only charged particles cause Cherenkov light and neutrinos, being neutral, will not cause this effect and pass through matter almost entirely unaffected unless they have extremely high energies and even then they interact via the weak force and not electromagnetism.
This i understand this far.
So now, i have this black hole that i can't see. I send an object toward it. From my perspective, time slows to a halt on the sent objective at the event horizon, so it looks like it never enters. So it actually stays visible, right? Over time, the black hole would look like a big ball of stuff frozen in time? What am i missing here?
This i understand this far.
So now, i have this black hole that i can't see. I send an object toward it. From my perspective, time slows to a halt on the sent objective at the event horizon, so it looks like it never enters. So it actually stays visible, right? Over time, the black hole would look like a big ball of stuff frozen in time? What am i missing here?
The red shift. Drop a flashlight down into a black hole (you'l need a big black hole so that tidal forces don't destroy the light on the way in). As it falls, the red shift increases rapidly and so the flashlight both reddens and dims rapidly. (That is, fewer photons per second AND each photon has lower energy.) After a short time near the event horizon, you will receive the last photon you will ever get from the flashlight - and the same is true no matter how bright the light. So, no, it is no longer visible as it falls in.
So Hillary and Bernie are quantum entagled AND faced with imminent Pauli Exclusion Principle issues!
Feel better now?
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
Thanks. All those "popular" explanations always only go so far as to exclaim "time slows for the object, so you never see it enter the event horizon" which misses this crucial info :)
Either you are admitting to murder or you don't know that 0 divided by 0 is undefined in most reasonable contexts.
Contribute to civilization: ari.aynrand.org/donate
So, one thing I don't understand about quantum entanglement. In the simplest terms, you can have 2 photons generated from a specific process, and if you measure the spin (polarization?) of one of the photons, the other one will always have the opposite spin. And that's what they call quantum entanglement, right? But to me it simply means that the said specific process always generates a pair of photons with opposite spin. Where is the magic of entanglement here? Please help me understand. It's kind of like if we take an apple and slice it in two, and then measure one of the halves, the other will always be facing the other way. Well, yeah, we just sliced an apple in two halves, so no surprise there, they'll always be facing each other. What am I missing?
a) entanglement does not transfer information faster than light. Why? if i send entangled pairs of photons from a to b and c, and b and c detect these photons, the photons took time to reach b and c. If b does something to the photon, the entanglement is lost. If b and c measure they will know the state the other one received, however they can not influence what is received in the other place, so sorry guys, no FTL transmission of information
b) What is weird about entanglement is actually not so much it statistical property of the correlation. If a packs a white and black marble in two packages and mixes the packages and sends them out, the result from the viewpoint of b and c will be the same - each one will know which marble the other one received. The weird property is that the state is prepared in a way that the two possibilities are quantum states, which can be subject to phase shift, transitions etc, and are "collective" in that sense that b and c can transfer their state to particles (and possibly create further entanglement) - the basis for Quantum key distribution networks - and that the information which exists exists only in the form of a shared posteriori observation. i.e. the classical marble can be looked at without destroying the correlation, while a quantum entangled photon will be entangled with your measurement apparatus when looking at it.
c) what these guys did-AFAIU (my topic was very far away) is to create a model system of a black whole, which tries to represent a black whole in a way which we assume it is, observed some properties which can be predicted from this model (temperature of emitted radiation), and checked for some others - correlation, where they found correlation which they interpret as entanglment.
d) While did not look into the details, i can say from my own experience that such experiments are tricky, and i find the interpretation a little vague. But i have to look closer. I did use quantum state/operator tomography, which usually is the benchmark measurement when you want to prove entanglement, or properties of the superoperators describing your quantum operations. I understand that this may not be possible in this case, which is why one can go for other phenomenological approaches
e) One should be careful. Proving entanglement is not so simple (Look for entanglement measures), and proving that is actually *survives* the event horizon, instead of being created there, may be very nontrivial. It could very well be that non-entangled state are transformed in entangled states to some degree.
THANK YOU for that explanation I was wondering the same thing for ever. That really helped thank you!
since entanglement is the like writing a 1 on one index card and writing a 0 on another, then dropping the envelopes into a box, grabbing one of the envelopes and opening it which reveals what the value of the card in the box is, I would expect this situation to be the case.
A billionaire businessman and a successful brain surgeon have nothing on you, right?
Get back to me when you match their success.
One has been divorced two more times than me than me and declared bankruptcy four more times and may or may not have more hair than me. The other can apparently sleep while standing, sitting and conversing and may or may not have tried to stab his friend (or relative) while trying to decide whether to accept his "scholarship" to West Point, before reminding a robber to rob someone else.
All in all, I think I'm doing pretty well - in comparison. Occupation, money and success aren't everything.
It must have been something you assimilated. . . .
I disagree. It would probably have lasted at least 6 months.
I think we've pushed this "anyone can grow up to be president" thing too far.
No. As things approach the event horizon the light from them is increasingly red-shifted, so that by the time they actually reach the event horizon it's been red shifted down to 0 hertz. Also, the light almost goes into orbit, so it needs to make an ever increasing number of orbital passes to escape to where you can see it, so eventually it takes it forever to get there. Both effects are happening at the same time.
Please note that this is an idealized scenario, and assumes perfect vacuum between you and the event horizon. In actuality there would be enough stuff to absorb the light before it reached you. It's possible that even virtual particles would suffice to absorb the light before it reached you as the end-point was approached.
I think we've pushed this "anyone can grow up to be president" thing too far.
How do they know it survives through the event horizon, were they there? -Ken Spam
You are talking about non-demolition measurements, but these are a different issue, since they do actually not leave the state undisturbed, but only do a "pure measurement" i.e. project its own state precisely into one of the conjugate variables of the quantum system, and leave the other one intact.
"and then the other — even if it's across the Universe — is immediately known"
Well I guess that's settled then. A year or two ago I posted that scientists potentially thought that quantum changes could occur faster than light because nothing is "traveling" it's merely updating to current reality in real time. People replied like crazy and downvoted me to oblivion. Well I guess we found out who was right after all, didn't we? In fact I recall a story about NASA wanting to test this onboard the ISS. I think that rocket carrying it exploded but still.
Quantum encryption protocol BB-84
You set up the experiment so that you can polarize a photon at 4 angles: 0, 45, 90 and 135 degrees ( | / - \ ).
There are two distant terminals, let's call them A and B, where the photons can be polarized and then checked whether they passed the polarizer or not. There's also a (dumb) source of entangled pairs in the middle, that sends one photon from the pair to each of the terminals.
Take a single (non-entangled) photon: If you polarize it at 0 degrees, it will pass the 0 degrees polarizer 100% of the time, 90 degrees 0% of the time, and the two diagonal ones 50% of the time. Extend to three other cases by rotating the initial polarizer by multiplies of 45 degrees; it's analogous.
Pass the same photon through three polarizers now: 0, 45 and 90 degrees. Unlike with just two (0 and 90) It will pass in 25% cases.
Take an entangled pair of photons. If you polarize one of them, the other behaves as if it was polarized the same as the first.
As entangled photons are sent, both A and B choose random orientations of their polarizers (each with own, locally generated random sequence); they write down the sequence: angle, result (photon passed or not).
Now the result is a string of zeros and ones each with an angle. If both randomly choose | or - then the result is valid, 1 means the other side had the same orientation, 0 means the other side had a perpendicular orientation. If one choose | or -, but the other choose \ or /, the result is random junk. The problem though is that neither of them knows which ones are right and which ones were faulty. There's a lot of data on both ends but none useful. No *actual* information was exchanged, because any that really did, was hidden behind the randomness of the polarizer setting.
Now, using normal, non-encrypted channels, A and B exchange the recorded random sequence of polarizer settings.
Each compares this with own recording and converts: Mine was |, their was |, got 1, record 1. Mine was |, their was -, got 0, record 1. Mine was -, their was -, got 1, record 1. Mine was |, their was / - discard record; it's junk.
And again, no information was passed from A to B because all the information was *generated*, in two copies at two ends. A couldn't send B a single bit. It's the dummy emitter that sent a random bit in two directions, and it was recorded on two ends. Still, to be actually read, it required normal subluminal exchange for decoding.
Nevertheless, both A and B now have the same sequence of bits, which they can use as a key for a common encryption - and they know the key had not been intercepted; no third party has it.
How do they know? Because for a third party to get any data from the photons, they'd need to put a polarizer along the way and since they don't know the sequence, they'd have to turn it at random.
Now remember the "three polarizers" case from the beginning?
"Mine was |, their was -, I got 1. Alarm! Somebody put a 45 degrees polarizer along the way! The communication has been intercepted!"
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
I've known a few. Whenever they are around, everything intelligent seems to get sucked away.
Hey be nice! I was ENGAGED to one!
Please don't remind me of the supply officer on that damn submarine!
Undefined, for 0/0, means that any value is permissible. For different uses, it can mean no value is permissible. In this case, 0% is a perfectly valid answer, since 0*0 = 0. Any other answer is possible; for example, 53.6% of the people I've stabbed with murderous intent survived.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Its undefined unless you define it.
- Division by zero does have a defined value of - imaginary infinite. That is a positive infinity and a negative infinity, or if you sum them together zero.
- An alternative derived using permutation also sums to zero, with the numerator becoming the remainder.. This is the value that computer ALU's would actually produce if allowed to calculate division by zero..
0/0 = 1 is just a formalism, and is technically incorrect because it produces a signed value from a signless operation.. A similar formalism is to assign the value of roots as positive when in reality their sign is by definition unknown. m^2 = n, root (n) = +m or -m.
Below the speed of light Special Relativity is one of the most accurate theories in physics - above the speed of light..
Oh boy if only it were that simple. Technically the modern definition of antimatter defines it as matter with positive mass but opposite charge. We can add another type of antimatter that has negative mass, but this isn't generally compatible with a lot of modern physics theory, which says that with negative mass you also get negative time. I'm working on a new physics model that solves this problem, but to do it the model has to replace general relativity at FTL speeds with a new modified 'absolute frame' model.. There's a reason that Einstein hated the FTL , its maths is complex disjointed and not pretty..
Below the speed of light Special Relativity is one of the most accurate theories in physics - above the speed of light..
0/0 does not equal 1, and anyone ever stating that it does needs to be shot in the fucking face.
Division by zero is undefined. It is not infinite - positive or negative. It is incalculable by the definition of the operation of division.
It is not a "formalism" to state anything other than the fact that it is undefined. It is not a formalism to state roots as positive values, either. Maybe I'm old, but I ALWAYS consider both positive and negative values unless I explicitly limit my domain. To do otherwise would be flat out fucking wrong.
You can dry run a computer division by zero operation, and the operation produces a result of zero leaving a remainder that equals the nominator. At its heart division is a multiple subtraction and the result is an accumulation therefore division by zero produces zero..
On the opposite when you do the formal theory of calculus you get to play with infinitesimals and zero, and the infinitesimals map the graph of division and multiplication by zero - to produce the familiar tangent curve. (summing the (+)(-) infinity to zero is my own observation) Quite a lot of complex maths in there, Riemann spheres, Riemann metric, inner products, etc.. https://en.wikipedia.org/wiki/... Cant say that I understand half of it myself, but its the maths that leads to tensor manifolds, Lie algebras, and General Relativity..
Below the speed of light Special Relativity is one of the most accurate theories in physics - above the speed of light..
Yeah, I'm better than the both of them put together.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"