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A Link Between Wormholes and Quantum Entanglement
sciencehabit writes "Theoretical physicists have forged a connection between the concept of entanglement — itself a mysterious quantum mechanical connection between two widely separated particles — and that of a wormhole — a hypothetical connection between black holes that serves as a shortcut through space (first abstract, second abstract). The insight could help physicists reconcile quantum mechanics and Einstein's general theory of relativity, perhaps the grandest goal in theoretical physics."
Since it is physics, perhaps we could trust it better if it was 'LaForged'.
Silence is a state of mime.
Unfortunately, it's not that simple. In the scenario you're describing, there is hidden information inside the envelopes, as the direction of the cards has already been determined. The quantum mechanical analog is this is so-called "hidden variables", aspects of the state of a system that we simply can't see. But experiments have ruled out this possibility, so quantum mechanics is actually much weirder than that.
If I can be modded down for being a troll, can I be modded up for being an orc, or a balrog?
That's too simplified (as is this reply).
It is not that one is A and the other B when posted; rather that they are each an AB, which, when revealed, resolves to an A or B. That resolution then also resolves the other, but, that information must be communicated "faster than light", which is currently not supposed to be possible (if FTL information transfer really worked, all sorts of wierd stuff ensues, incuding the possible destruction of the universe).
By proposing a sort of "worm hole" which, in effect, creates a single particle string with just the endpoints noticable by us as distinct particles, the entangled endpoint-tunnel-endpoint can transfer information outside the four-dimensional universe' ligh-speed limitation.
Relativity has little to do with dark matter or dark energy -- the matter content is irrelevant, since relativity only really dictates the geometry; basically you have an equation G=T, where G is the geometry and T the matter; what that matter *is* is something for someone else to worry about. It has absolutely damn all to do with the Higgs. The Higgs field is a part of the standard model of particle physics that gives fundamental particles their mass. It has absolutely nothing to do with relativity at all; if it did, we would already have a quantum field theory that was general relativistic in nature, and we'd all be laughing. Or crying, since many of us would now be out of a job.
Quantum electrodynamics throws out infinities as a matter of course. This worried a lot of people, and then "renormalisation" was invented. It basically says "if you see a number multiplying an infinity, just write it as another number". The best example is the electron mass. What we see is actually m_electron * infinity. So we "renormalise it", and say that m_electron is actually m_bare electron * infinity.
It was either Feynman or Schwinger - probably both - who expressed serious doubts about the mathematical validity of renormalisation. Thing is, as they also acknowledged, it works. QED is the most accurate theory we currently possess, so despite the air of bullshit that surrounds renormalisation something's obviously working fine.
The issue comes when you have theories that are non-renormalisable, so you can't ditch the infinities this way. Quantising general relativity typically leads to a non-renormalisable theory. That's where all our problems have been for the last sixty years...
The observation effects the outcome. So in your example, the envelopes were sent with blank pieces of paper. You use scissors to open one letter, resulting in a nice snowflake design on the piece of paper. The other paper is now a dead cat, poisoned by the vial broken by your hubris.
At a certain point quantum physics causes a spooky action in the space between my ears leading to a "Duh, what the heck/" experience.
No it is much more interesting. What you describe is just classical entanglement. Quantum entanglement is more interesting, because you can do things you can't do classically: To see this, try to solve this riddle: A team of three persons is brought to the city of Zuerich and given the following challenge: They are allowed to discuss and then they will be brought to Paris, Rom, and Berlin, an either all of them will be shown a card with an X on it, or else, only one of them will be shown a card with an X and the other two of them will be shown a card with a Y. Each of them will answer with '-1' or '1', but they are not allowed to communicate by phone (or in any other way). If they have been shown three Xs, the product of all answers must be '1'. Else, the product of the answers must be '-1'. If the product of the answer is wrong, they will get killed (because good riddles have to be gruesome). What strategy does allow them to survive this challenge with certainty? Hint: Only quantum physicists can do this.
It just looks like it's in 2 seperate places at once. This would solve the whole "faster than light speed communication" problem pretty easily if they could come up with a theory utilising extra dinensions to explain it.
I'm the first to admit that anything quantum blows a wormhole through my head. I struggle to find anything that will allow me to grasp it. I'm a programmer, dammit.
"God doesn't play dice with the Universe"
OK, whatever.
Maybe, just maybe, "God doesn't waste CPU cycles rendering windows that are trivially culled from the scene graph".
So. When you observe the particle its window comes to the top and The Program has to do all the rendering calculations.
Cue attempt by actual physicists to explain why this attempt to grasp the concept is totally inadequate or the more enjoyable funny bits about how the Universe is written in either Lisp or Perl.
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
The key here, is "resolves to".
That phrase means: "when we're trying to compute the state (A or B), we can't work out the formula until it arrives. (because we don't have enough information) - and when they arrive, bam! do the math, and the result is, A or B."
Math works that way. It's a model for a physical process in nature. The actual mechanism for that physical process? We don't know. And all theories are impossible. (involve FTL travel).
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
I think the real riddle here is to parse your riddle.
This action at a distance nonsense just has to end someday. This is no such thing implied by Bells theorem or entanglement experiments such as those by Aspect. Just let it go. Entanglement just explores the non-classical nature of quantum probability. The outcome of experiments with entangled particles is predicted by the standard Dirac notation and no mysterious action is needed.
I'm not a physicist, but I've played Portal and Portal 2, and I also concur. I plan to play Quantum Conundrum tonight, to make more detailed observations of the phenomenon. I will publish my findings.
My PhD is in Literary Theory, so I can likewise confirm the "weirder than that" part, because that was kinda my specialty.
You are welcome on my lawn.
Note: I am not a physicist.
Analyzing conflicting reports from other physicists on the true nature of Quantum Entanglement, I can confirm for you that a good percentage of them really want it to be this simple, and for nothing "spooky" to be happening at a distance, and will just about always fucking wig out on you if you point out the other physicists' views that it is in fact much weirder than that, and spooky stuff IS in fact happening at a distance.
I am not a physicist.
But I keep hearing that there is actually nothing mysterious about entanglement at all... Something along the lines of:
You post 2 envelopes containing cards in opposite directions, one with a printed letter A, the other card with the letter B.
At one destination, the envelope is opened to reveal the letter A. ... then through some mysterious quantum mechanical connection.... you know that the envelope at the remote destination contains the letter B.
And that's about all there is to entanglement....
Can any physicist confirm?
I'm not a physicist, just a well-read layman, but...
It is more mysterious than that, but if you go with the Many Worlds interpretation it's not much more mysterious.
Basically, if you entangle letters A and B and send them in opposite directions, you're really creating two universes corresponding to the two possibilities: universe P (A here, B there) and universe Q (B here, A there). If you open the envelope to reveal A, for instance, then that copy of you in universe P now knows they exists in universe P, and likewise for B and Q. But unlike in classical physics, universe P is not completely separated from universe Q. P and Q still exist as a single mathematical object, P-plus-Q, and you can manipulate that mathematical object in ways that don't make sense from a classical standpoint.
Basically, it all comes down to one small thing with big consequences. The real world is NOT described by classical probability (real numbers in the range [0,1]). Instead, the real world is described by quantum probability (complex numbers obeying Re[x]^2 + Im[x]^2 = 1).
As it turns out, "system P-plus-Q has a 50% chance of P and a 50% chance of Q" is really saying "system P-plus-Q lies at a 45deg angle between the P axis and the Q axis". Starting from P-plus-Q, you can rotate 45deg in one direction to get orthogonal P (A always here), or you can rotate 45deg in the opposite direction to get orthogonal Q (B always here), thus deleting the history of whether A or B was "originally" here. (If P and Q were independent universes, this would decrease entropy and thus break the laws of physics.) Even more counterintuitively, you can even rotate P-plus-Q by 15deg to get a 75% chance A is here and a 25% chance B is here (or vice versa, depending on which quadrant the starting angle was in). Circular rotations in 2-dimensional probability space are the thing that makes quantum probability different from classical probability, and thus the thing that makes quantum physics from classical physics.
Classically, A is either definitely here or definitely there, and until we open the envelope and look we are merely ignorant of which is the case. Classical physics is time-symmetric, and it therefore forbids randomness from being created or destroyed; classical probability actually measures ignorance of starting conditions. In a classical world obeying classical rules, you can't start from "50% A-here, 50% B-here" and transform it into "75% A-here, 25% B-here" without cheating. The required operation would be "flip a coin; if B is here and the coin lands heads, swap envelopes", and you can't carry that out without opening the envelope to check if B is here or not. Quantum physics is also time-symmetric and also forbids the creation and destruction of randomness, but quantum probability (also called "amplitude") is not a mere measure of ignorance. In the Many Worlds way of thinking, physics makes many copies of each possible universe, and the quantum amplitude determines how many copies of each universe to make. At 30deg off the P axis, cos(30deg)^2 = 75% of the copies are copies of universe P, and you experience this as a 75% probability of finding yourself in a universe with "A here, B there".
(Or something like that. It'll pr
Range Voting: preference intensity matters
that made milk come out my nose... and I'm not even drinking milk.
That seems a good example of entanglement (quantum or not) weirdness.
Questions raise, answers kill. Raise questions to stay alive.
this is about a condescending phrase you tossed off about laymen and how analogies give them wild notions...
and that is ***exactly*** how the tachyon anti-telephone works
someone with a fucking PhD saw the same behavior as the layman, and made a theoretical faster-than-light telephone design based on it
bottom line is that you're wrong in saying that analogies are bad because they give laymen wild ideas...in fact they have **pretty fucking cool ideas**
Thank you Dave Raggett
To expand on your reply, here's a different letter game.
you mail two letters with magic XY cards inside. When the first letter is sliced open the probability it shows and X or a Y is equal. If the first letter is sliced open left to right then the other letter will match the contents of this letter. If you open it right to left then the other letter will show the opposite letter.
There's no way the contents of the letters can predetermine the outcome. (i.e. No hidden variables can explain all the possible outcomes). Notice also that this can't be used to transmit information faster than the speed of light. But by doing the experiment we can confirm that the choice of which way to slice changed the outcome of the remote envelope.
Some drink at the fountain of knowledge. Others just gargle.
Something that's a little bothersome is that when you are designing a video game that portrays a classical world, the physical limits of the computer end up imposing many of the physical laws we are used to.
for example, consider diffraction limited resolution. Basically the further away something is, the less resolved it becomes. The bigger the eye or telescope you look through the more you can resolve at a distance. In the real world we call this diffraction limited resolution. In a computer game we call it pixels, and the bigger the monitor (in pixels) the better the resolution.
To object oriented variables cannot simultaneously know each other's state. One of them has to be updated first. There's a finite limit on how fast the computer can alter the memory locations and it can't change both at the same time. So there's a kind of speed of light limit on how fast the world can change. If were doing this on distributed architectures or iterating serially over the objects then that limit actually shows up in the connectivity of objects with distance: nearer objects can influence each other sooner than remote objects.
Finally, there is an exception to that rule. Two objects can communicate instantly if they share the same class variables. This is spooky action at a distance. While it's often claimed that quantum mechanics does not allow hidden variable theories , this is a mis-interpretation of Bell's theorem. In fact it only disallows local hidden variable theories. Global hidden variable theories are what QM says do exist. That's exactly how you get entanglement.
So QM emerges because of the class variables, diffraction emerges because of memory limits and the speed of light comes out from serial processing at the CPU or memory access level.
Thus you can't actually create a simmulation of reality that didn't have the characteristics of our weird world even if you wanted to.
Some drink at the fountain of knowledge. Others just gargle.
A little insight from the experts should help to clarify:
* Quantum mechanics is magic.- Daniel Greenberger.
* Everything we call real is made of things that cannot be regarded as real. - Niels Bohr.
* Those who are not shocked when they first come across quantum theory cannot possibly have understood it. - Niels Bohr.
* If you are not completely confused by quantum mechanics, you do not understand it. - John Wheeler.
* It is safe to say that nobody understands quantum mechanics. - Richard Feynman.
* If [quantum theory] is correct, it signifies the end of physics as a science. - Albert Einstein.
* I do not like [quantum mechanics], and I am sorry I ever had anything to do with it. - Erwin Schrödinger.
* Quantum mechanics makes absolutely no sense. - Roger Penrose.
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
By proposing a sort of "worm hole" which, in effect, creates a single particle string with just the endpoints noticable by us as distinct particles, the entangled endpoint-tunnel-endpoint can transfer information outside the four-dimensional universe' ligh-speed limitation.
It seems like they're getting closer, but isn't it still harder to think of an infinitely long wormhole connecting the two ends than to consider that the topology we experience isn't the fundamental one and those ends are still local in the 'real' topology, and not stretched to the bounds of the universe?
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Imagine 2 envelopes, A and B. Inside both envelopes is a hidden binary code, just printed on a card.
01001101000101101011011011.
These envelopes are sent to Alice and Bob. However, Alice doesn't read the code directly. She first generates her own pseudo random stream of random 0's and '1's. She can control the ratio of 1's and 0's, by initially choosing an angle, and the Generator will spew out a sequence that all '0's if the angle is 0degrees, or all '1's if the angle is 90degrees, and any angle between 0 and 90 will adjust the ratio accordingly.
Alice then X'ORs her stream of 0's and 1's with that printed on her card, in the envelope, to give a result.
At the other envelope, BOB does exactly the same. He also has a pseudo random number generator, (using the same seed as Alice). When he sets his angle to 0, and Alice sets her's to 0, they will BOTH end up with the same sequence on the PRNG, and so XORing the number on the card will result in the same message. In fact when Alice and Bob set their PRNG to the same angle, they always will get the same sequence, and so their message will always match. Nothing spooky going on here.
The spooky thing happens when Alice and Bob choose different angles. Lets say that Alice sets her angle to 0 degrees, and Bob chooses 30 degrees. They do the calculation, and it appears the final sequences correlate 3 out of 4 times.... or 25% of the time there is a difference between Bobs and Alices code. Bob then changes his angle back to 0, and Alice sets hers to -30 Degrees. Again, after doing the calculation, they work out that 25% of the time the codes differ.
If alice sets hers to -30 and Bob sets his to 30, it would be common sense to say that there could be no more than 50%, the codes will differ. Except this is not the case. In the real world, using real entangled particles the result comes out to be 75%. What *must* be happening for this result, is the original hidden code printed on Alices and Bob's card MUST some how change, when the other party changes their angle.... OR, that there is no hidden code, but something else is going on... No hidden fixed sequence of numbers can explain the experimental results. This is 'Spooky' action at a distance, and can't be explained using traditional physics on its own.
> You post 2 envelopes containing cards in opposite directions,
> one with a printed letter A, the other card with the letter B.
BZZZZT.
You have 2 envelopes, one contains an "AB" and the other contains a second "AB". When you open the first envelop, the AB *turns into an A*, and the other envelope *instantly turns into a B*.
What you are describing, where the contents have actual values before measurement, is known as "hidden variables". Einstein liked it. However, Alain Aspect demonstrated the universe simply doesn't work that way.
The insight could help physicists reconcile quantum mechanics and Einstein's general theory of relativity
What? QM is COMPLETELY in line with relativity. If you had FTL communication, it wouldn't, but that doesn't exist- quantum teleportation requires a classical channel to relay information (namely, which state Bob's particle collapsed into). I admit I haven't read the linked articles yet, but I doubt the authors made any such claim (and that was input by the submitter/editor)
Source: I am a PhD student in Quantum Computer Science.
Exactly, you can coordinate but not communicate. Which is still allowed by causality and special relativity. Isn't it amazing?