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Einstein's 'Spooky Action' Has Been Demonstrated On a Massive Scale For the First Time (sciencealert.com)
schwit1 shares a report from ScienceAlert: For the first time, scientists have managed to show quantum entanglement -- which Einstein famously described as "spooky action at a distance" -- happening between macroscopic objects, a major step forward in our understanding of quantum physics. Quantum entanglement links particles in a way that they instantly affect each other, even over vast distances. On the surface, this powerful bond defies classical physics and, generally, our understanding of reality, which is why Einstein found it so spooky. But the phenomenon has since become a cornerstone of modern technology. Still, up until now quantum entanglement has only been demonstrated to work at the smallest of scales, in systems based on light and atoms, for example. Any attempt to increase the sizes has caused problems with stability, with the slightest of environmental disturbances breaking the connection. But new research changes all of this, by demonstrating that this "spooky action" can indeed be a reality between massive objects. We're not talking massive in the black hole sense but in the macroscopic sense -- two 15-micrometer-wide vibrating drum heads. And the next step will be to test whether those vibrations are being teleported between the two objects. The research has been published in the journal Nature.
Entanglement is a cornerstone of modern technology? Say what?
Massive is relative.
15 micrometer is only 0.015 mm. Massive would be 1,500 meters.
0.015 mm is massive compared to 10^-10 m.
Context matters.
>which is why Einstein found it so spooky
Which is why you have no clue what Einstein was talking about. He wasn't spooked you knucklehead, he was mocking it as magic.
Did I miss a bunch of modern technology development?
Never underestimate the bandwidth of a 747 filled with CD-ROMs.
It's just our 12-dimensional overlords toying with us.
>"In quantum teleportation, properties of physical bodies can be transmitted across arbitrary distances using the channel of 'spooky action at a distance'," says one of the team, Caspar Ockeloen-Korppi from Aalto University in Finland.
This is a fundamental misunderstanding of entanglement. It is not a mechanism for teleportation, it is a dual destination verification mechanism (ie. one must be opposite the other if they maintain entanglement). You cannot set the value at one end and have it appear on the other.
For those of us who don't know enough to really understand it, we can think of it like a cat.
You pull the cat's tail on one end, the cat meows on the other end. Quantum entanglement is exactly like that. Except there is no cat.
(The above is an old description of radio, often attributed to Einstein. Doesn't sound like Einstein's sense of humor, though.)
Actual physicists, please correct me if I'm wrong:
Yes it apparently is faster than light in a vacuum, but it doesn't seem to matter. The change in spin happens instantaneously at both places, but since you can't deliberately change the spin yourself, merely observe it, no information is actually propagated. Thus you're not transmitting anything faster than light, and the universe therefore doesn't explode.
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
I find the summary in great need of clarification. Let me attempt to clarify it in the hope that will be useful to other readers.
First, the linked article links to a much better summary written by one of the team members, Matt Woolley. I recommend you read it instead:
https://theconversation.com/ex...
Second, the summary conflates *mass* with *distance*. The experimenters claim to have entangled remarkably massive objects (compared to the mass of atoms, for example). But the summary says 'any attempt to increase the sizes has caused problems with stability' and that, taken literally, is not true. For example, here's an experiment from 1998 in which entanglement was maintained over a distance of kilometers:
https://en.wikipedia.org/wiki/...
Finally, the summary claims 'a major step forward in our understanding of quantum physics' but I doubt that. It sounds to me like a major accomplishment but one that *confirms* our previous understanding of quantum physics in more massive systems.
It's not quite the same as the cold fusion. With cold fusion there wasn't any cold fusion and some combination of noise and bad experimental setup made it look like there was. With entanglement, the entanglement part is not actually science. There isn't any way to disprove that measuring one particle affects the other particle. Science requires that a hypothesis be falsifiable.
Or try this older-technology test, which is equivalent:
1) Obtain two empty boxes
2) Into the first box, place a red marble and a blue marble
3) Put on a blindfold so you can't see anything
4) While blindfolded, reach into the box with the marbles and take out one of the marbles, and put it into the other box
5) Close both boxes and seal them shut
6) Remove the blindfold
7) Mail one of the boxes to Alpha Centauri
8) When it gets there, open the box you didn't mail, and note what color marble is in it
9) Enjoy the "faster than light communication" -- you just "instantaneously" learned the color of a marble located four light years away!
I don't care if it's 90,000 hectares. That lake was not my doing.
Convert it into Planck lengths and you'll see.
Actually, not quite. For the analogy to work, each half of the coin is equally heads and tails until the measurement. Only the entanglement itself (i.e. that one is opposite the other) was encoded in the envelope to begin with.
We might need another analogy. Consider Donald Trump and Hillary Clinton as entangled particles guaranteed to hold opposite views on any given topic. With Hillary in New York and Donald in Los Angeles, ask Donald a question about one of the few things he has no opinion on. Until you ask, nobody (including Donald and Hillary) can know what his answer will be. But as soon as you ask and he answers, we Know what Hillary thinks about the subject as well.
Now, at this point, Donald and Hillary have taken Stands on the issue. Before the question was asked, each of them equally supported and opposed the issue. Once the question was asked, one fully supported and the other fully opposed the issue. If you then manage to convince Donald to change his mind, your efforts destroy the entanglement, so it will not change Hillary's opinion.
You ignores the very basic idea of entanglement that is: "If I change a property of a entangled particle (spin, polarization, etc), that state automatically reflects on the other particle".
That's not how it works. You can read a property of a particle, and learn something about its entangled pair.
But if you change a property, you break the entanglement.
Improving the analogy a little:
1. Get two WHITE marbles, each with the property that if you shake it, it will randomly turn blue or red.
2. Put the marbles in boxes and mail one box to Alpha Centauri. Wait until you know it has arrived.
3. Open your box and shake your marble, and watch it become red. Now you know that the other marble will turn blue, or already turned blue as your fellow Alpha Centauri scientist shakes or shook his marble. This is because of a law of nature dictating that the total number of blue and red marbles in the Universe must balance.
Nobody can tell in a meaningful way who shook his marble first. Depending on the velocity of the observer, it could be either one of you who "instantly" programmed the other marble to assume the opposite color. (This is the part that most people forget when describing the spooky instantaneous, FTL action at a distance.)
Remember once more, none of you had any control over what color your marble turned.
Anyone of you may instead paint your marble to force it into the color of your preference, but that breaks the quantum spooky action at a distance. If/when your fellow shakes his marble, it may assume any color. But your fellow won't know the difference until you tell him that you cheated.
If you later communicate with your fellow and learn that his marble turned the wrong color, it just means that the marbles failed to become properly entangled.
There is no substitute for common sense. Especially, no body of rules will do.