HomeLatest ThreadsGreatest ThreadsForums & GroupsMy SubscriptionsMy Posts
DU Home » Latest Threads » Forums & Groups » Main » General Discussion (Forum) » physicists measure speed ...

Fri Mar 8, 2013, 02:34 AM

physicists measure speed of Einstein’s ‘spooky action at a distance’: At least 10k x speed of light

Chinese physicists measure speed of Einstein’s ‘spooky action at a distance’: At least 10,000 times faster than light

A team of Chinese physicists have clocked the speed of spooky action at a distance — the seemingly instantaneous interaction between entangled quantum particles — at more than four orders of magnitude faster than light. Their equipment and methodology doesn’t allow for an exact speed, but four orders of magnitude puts the figure at around 3 trillion meters per second.

Spooky action at a distance was a term coined by Einstein to describe how entangled quantum particles seem to interact with each other instantaneously, over any distance, breaking the speed of light and thus relativity. As of our current understanding of quantum mechanics, though, it is impossible to send data using quantum entanglement, preserving the theory of relativity. A lot of work is being done in this area, though, and some physicists believe that faster-than-light communication might be possible with some clever manipulation of entangled particles.

Now, thanks to these Chinese physicists — the same ones who broke the quantum teleportation distance record last year — we know that spooky action at a distance has a lower bound of four orders of magnitude faster than light, or around 3 trillion meters per second. We say “at least,” because the physicists do not rule out that spooky action is actually instantaneous — but their testing equipment and methodology simply doesn’t allow them to get any more accurate.

http://www.extremetech.com/extreme/150207-chinese-physicists-measure-speed-of-einsteins-spooky-action-at-a-distance-at-least-10000-times-faster-than-light

33 replies, 6257 views

Reply to this thread

Back to top Alert abuse

Always highlight: 10 newest replies | Replies posted after I mark a forum
Replies to this discussion thread
Arrow 33 replies Author Time Post
Reply physicists measure speed of Einstein’s ‘spooky action at a distance’: At least 10k x speed of light (Original post)
The Straight Story Mar 2013 OP
apocalypsehow Mar 2013 #1
MjolnirTime Mar 2013 #2
apocalypsehow Mar 2013 #3
sofa king Mar 2013 #30
Fearless Mar 2013 #9
Duer 157099 Mar 2013 #22
Warren DeMontague Mar 2013 #4
RagAss Mar 2013 #23
white_wolf Mar 2013 #5
bhikkhu Mar 2013 #6
OldDem2012 Mar 2013 #7
burrowowl Mar 2013 #21
longship Mar 2013 #10
redgreenandblue Mar 2013 #12
Javaman Mar 2013 #13
Kablooie Mar 2013 #8
bigtree Mar 2013 #15
ljm2002 Mar 2013 #16
hunter Mar 2013 #17
Thor_MN Mar 2013 #11
hunter Mar 2013 #14
Thor_MN Mar 2013 #19
hunter Mar 2013 #20
Thor_MN Mar 2013 #25
hunter Mar 2013 #29
Thor_MN Mar 2013 #33
Jamastiene Mar 2013 #18
RagAss Mar 2013 #24
DCBob Mar 2013 #26
1-Old-Man Mar 2013 #31
Berlum Mar 2013 #27
Hulk Smash Mar 2013 #28
MineralMan Mar 2013 #32

Response to The Straight Story (Original post)

Fri Mar 8, 2013, 02:39 AM

1. Such speeds would actually make interplanetary travel outside our Solar system somewhat more

feasible, if they could somehow be replicated without time differential problems (along with a whole boatload of other stuff).

Reply to this post

Back to top Alert abuse Link here Permalink


Response to apocalypsehow (Reply #1)

Fri Mar 8, 2013, 02:42 AM

2. such speeds make time travel possible, for information at least

 

Reply to this post

Back to top Alert abuse Link here Permalink


Response to MjolnirTime (Reply #2)

Fri Mar 8, 2013, 02:56 AM

3. +186,282.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to MjolnirTime (Reply #2)

Sat Mar 9, 2013, 03:42 PM

30. Wouldn't that be strange.

A stock-ticker that sends its own data back in time would make its owner fabulously rich three seconds ago. I suppose that multiverse theorists could even chart a course around time paradoxes by pointing out that the messages may actually come from another, very similar universe, not our own.

It potentially makes exploration of other solar systems easier as well. Entangled particles could be sent out on an exploration vehicle, which would take decades to get somewhere else, but once there information could be nearly instantly sent back and forth. I suppose that if you had enough entangled particles you could even control the exploration vehicle in real-time... from the past... is that right? Or perhaps one could "teleport" designs for something--or someone--to the exploration vehicles once they have arrived.

That might skirt the biggest problems of human interstellar travel, which is surviving an absurdly dangerous decades-long journey with a society still intact at the end. If you can just zap them aboard or propagate them from test tubes once there, with a reliable information feed to other humans, most of the requisites for successful colonization are met.

But I don't know what I'm talking about. I'd better leave this subject to the physicists.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to apocalypsehow (Reply #1)

Fri Mar 8, 2013, 04:34 AM

9. Acceleration would be a big problem

You wouldn't want to arrive as a pool of atomic sized goo.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Fearless (Reply #9)

Sat Mar 9, 2013, 12:13 AM

22. Says you

You're not the boss of me.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Fri Mar 8, 2013, 02:59 AM

4. according to the Copenhagen interpretation, it HAS TO BE instantaneous.

Last edited Sun Mar 17, 2013, 01:41 AM - Edit history (1)

That's the whole point. It's not about "sending" information, it's that locality itself is called into question; the notion that any two points, separated by space OR time, are really 'separate' at all.


remdi95

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Warren DeMontague (Reply #4)

Sat Mar 9, 2013, 12:38 AM

23. Exactly.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Fri Mar 8, 2013, 03:09 AM

5. So if I'm understanding this right...

that means the whole idea that the speed of light is a kind of a universal speed limit is false at least at the molecular level?

Reply to this post

Back to top Alert abuse Link here Permalink


Response to white_wolf (Reply #5)

Fri Mar 8, 2013, 03:15 AM

6. Its rather that the concept of space doesn't apply to quantum entaglement

which has its implications (and I'm no great expert), but that particles themselves can exceed the speed of light isn't one of them.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to white_wolf (Reply #5)

Fri Mar 8, 2013, 03:18 AM

7. That's what I'm getting from all of this too. As Spock would say, "Fascinating."....

...science is getting closer to science fiction every day.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to OldDem2012 (Reply #7)

Sat Mar 9, 2013, 12:04 AM

21. Yup!

Reply to this post

Back to top Alert abuse Link here Permalink


Response to white_wolf (Reply #5)

Fri Mar 8, 2013, 05:03 AM

10. Nope, that would be incorrect.

The speed of light still applies to particles at the molecular level, as you put it. It just doesn't apply to quantum entanglement, which is an entirely different thing. We're talking about the properties of particles, not the particles themselves.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to white_wolf (Reply #5)

Fri Mar 8, 2013, 06:16 AM

12. Quantum teleportation cannot be used to transmit information.

Information always travels slower than the speed of light.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to white_wolf (Reply #5)

Fri Mar 8, 2013, 10:16 AM

13. Well, you know what sammie hagar once said...

"I can't drive...186,000 miles per second!!!"

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Fri Mar 8, 2013, 03:21 AM

8. Could it be that the two entangled particles are actually the same particle?

Since multiple unseen dimensions are part of contemporary physics discussions, might a particle pass through an as yet unidentified dimension that allows it to appear in two positions in our dimension?
This would be a kind of wormhole dimension that enters our dimension in two different places.

It is essentially the same particle so when you do something to one, the other instantly reacts because it's the same particle.
This way it doesn't affect relativity at all because there is no transmission of information and no speed at all, the particle remains stationary.

It is our viewing of the particle that is split.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Kablooie (Reply #8)

Fri Mar 8, 2013, 11:13 AM

15. +1

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Kablooie (Reply #8)

Fri Mar 8, 2013, 11:28 AM

16. I don't think that's it...

...because the way they test the hypothesis is to spin one of the particles one way, and then test the other particle to determine its spin. The second particle's spin has to be the opposite direction in order to preserve the relationship of the two particles and prove they affect each other even though they have been split off from one another.

Of course there's more nuance to the experiment than that, but the main thing is, if it was one particle then both would have the same spin when measured; while the positive result of the experiment depends upon them having opposite spin when measured.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Kablooie (Reply #8)

Fri Mar 8, 2013, 11:47 AM

17. I always liked that idea.

My intuition (and I DO NOT have the math to back it up, so it's not science) is there is no "dimension" of time. The speed of light isn't a maximum speed, it's the ONLY speed. Everything is going at the speed of light, you, me, photons from the sun, our galaxy, and "distant" galaxies.

Our science describes a biologically evolved mode of perception. We're describing stuff the way we see it, stuff that keeps life coherent, and it couldn't be any other way. The universe is a very big place and there are "dimensions" (if you want to call them that) that are invisible to us. In comparison our minds are very small. Thus our models of the universe will always be grossly incomplete.

If "we" ever do exceed the speed of light it won't be as biological beings made of meat, instead we will be some sort of intelligence that can shift its perspective around and we will no longer be human.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Fri Mar 8, 2013, 05:40 AM

11. It is not a great analogy, but think of marbles

 

that exist only as pairs, one red, one blue. You pull one of the pair out of a bag, but don't look at it. You send the bag some distance away, then look at the one you pulled. What they are "measuring" is the speed that the one you sent away "turns the opposite" of the one you have... It more complicated, but there are arguments that they were always opposite in color so there is no speed to measure.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Thor_MN (Reply #11)

Fri Mar 8, 2013, 11:04 AM

14. That's not the way it works though.

The marble isn't red or blue until you pull it out of the bag.

It's more like you have two gray marbles in the bag. When you pull one out of the bag it randomly becomes blue or red, and instantaneously the other becomes it's opposite.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to hunter (Reply #14)

Fri Mar 8, 2013, 09:33 PM

19. But then there isn't much distance the way you do it.... Reread what I posted.

 

You select a marble but do not look at it... It's "gray" until you look at it, but it can be argued that it was always red or blue, you just didn't know which until you looked at it.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Thor_MN (Reply #19)

Fri Mar 8, 2013, 11:53 PM

20. Except it's not. The state of each particle is undefined until the state of one has a consequence.

And that consequence, red or blue, is entirely random, not because we can't see some hidden state, but because that state simply does not exist until the state is determined. When one particle or the other is forced to declare a state, and the other takes on the opposite state, these forced declarations are entirely random in the same way that the disintegration of the nucleus of a radioactive element is random, or more basically, how the behavior of photons or electrons in a a single and double slit experiment is inexplicable using classical mechanics.

If you are a photon, electron, or some other elementary particle you are neither heads or tails until somebody asks. When they do ask you take a coin out of your pocket, flip it fairly, and take on the state of whatever the coin shows, heads or tails. Meanwhile, your partner, who could be halfway across the galaxy, instantaneously takes on the other state. Since this determined state is entirely random from the perspective of everyone, no information can be transmitted by this means.

Wikipedia's got this on the single/ double slit experiment and the same sort of explanation applies to quantum entanglement:

Časlav Brukner and Anton Zeilinger have succinctly expressed this limitation as follows:

The observer can decide whether or not to put detectors into the interfering path. That way, by deciding whether or not to determine the path through the two-slit experiment, s/he can decide which property can become reality. If s/he chooses not to put the detectors there, then the interference pattern will become reality; if s/he does put the detectors there, then the beam path will become reality. Yet, most importantly, the observer has no influence on the specific element of the world that becomes reality. Specifically, if s/he chooses to determine the path, then s/he has no influence whatsoever over which of the two paths, the left one or the right one, nature will tell h/er/im is the one in which the particle is found. Likewise, if s/he chooses to observe the interference pattern, then s/he has no influence whatsoever over where in the observation plane he/she will observe a specific particle. Both outcomes are completely random.


Once you've played around a bit with the particle/wave nature of electrons and photons, the weirdness of quantum mechanics isn't any more explicable, but you do realize quantum mechanics is weird and unrelated to everyday experience.

I can spend hours playing with laser pointers. If you shine a laser through something like a window screen or a kitchen strainer onto a white wall you get a pattern like this:



You think you can explain it, but then if you move the screen or the laser, it's because the shadows and reflections you thought you were seeing move the wrong way.

This sort of quantum mechanics is real in a practical sense, engineers and scientists have to deal with it in the chips and hard drives of the computers we are using, but nothing is going to make it not weird, because weird quantum things simply don't happen on the scale of our ordinary lives. We see the cats without a grin, but not the grins without a cat.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to hunter (Reply #20)

Sat Mar 9, 2013, 06:50 AM

25. I said it wasn't a perfect analogy in the first post, you may have missed that.

 

Do some reading on Bell's theorem and you will note that what I have said is correct, while almost everything says the marbles are "gray" it has not yet been decisively proven that they are. In other words, there are arguments that they were always opposite in color.

The "grayness" of the marble that I pulled from the bag stems from the fact the it could be red or blue, I don't know yet because I have looked yet. You haven't looked yet either, so your marble is also "gray". The instant one of us looks, the "grayness" of the the other's disappears, even if the second marble hasn't been looked at. It doesn't matter how far apart we travel, if I look and find mine is red, it is instantly 100% that you have a blue marble. Nothing travels between us to turn the other marble the opposite color, they always were.

That said, this oversimplification is a classical physics example and not truly a quantum mechanical example. Quantum mechanics says that the objects are truly "gray", but has not been completely settled.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to Thor_MN (Reply #25)

Sat Mar 9, 2013, 03:15 PM

29. The double slit experiment with individual electrons suggests the marble is gray.

The entanglement of two particles is answered with "Red or Blue" in your analogy. Other experiments at this scale do not have simple "Red or Blue" answers. For example, the behavior of individual electrons passing through a double slit.

Here's how electrons sort out if they are launched one at a time through a double slit:

http://en.wikipedia.org/wiki/Double-slit_experiment

You end up with the same interference pattern you get with light.

It's a bit much to ask that all these electrons are impressed with some invisible state that predetermines their behavior if an experimenter should happen to place a double slit in their path. The more elegant explanation is that each electron is interfering with itself as it passes through both slits as a wave.

In a similar fashion it is the more elegant to say the state of each particle in an entangled pair is undetermined. Occam's razor isn't always the best tool to use, but in this case should you decide this state is already determined but hidden at the instant of entanglement you end up with an explanation of the cosmos where "it's turtles all the way down" or my favorite, that we live in a one electron universe, which makes it a very, very busy electron.

People are intuitively comfortable with light as waves, which is how we ended up with ether theory and such, but we are less comfortable with massive "particles" such as electrons, entire buckyball molecules, or even "solid" beings such as ourselves as waves. We don't want to see ourselves as tiny ripples of energy on the surface of an unimaginably large and highly energetic universe.

I'm a fan of John Cramer's work because it makes me think. Unlike myself, who can only spin analogies, he can do the math. If we are lucky his lines of experimentation will break some of the commonly accepted theories of everything.

http://faculty.washington.edu/jcramer/NLS/NL_signal.htm

Personally I don't think time travel or faster than light travel is possible simply because time itself does not exist except as an artifact of our own perception and physical state. We can say to ourselves, "Look, I won't sleep there because a bear might eat me" but we never say, "Look, I won't sleep there because a bear ate me." But it's possible those two statements have the same meaning. It seems likely to me the past isn't pinned down in place any more than the future is. If the past is as fluid as the future appears to be, how would we know? We only exist in the present.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to hunter (Reply #29)

Sat Mar 9, 2013, 06:07 PM

33. You have done a double slit experiment with marbles?

 

What the hell did you use to shoot them?

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Fri Mar 8, 2013, 11:56 AM

18. They are like twins or soul mates who have an inverse reaction to each other's experiences?

Physics was never my strongest subject. I understand some things, but a lot of it confuses me. I am still fascinated by it though.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Sat Mar 9, 2013, 12:40 AM

24. Time and space are properties of perception. Not real entities.

There is no locality.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Sat Mar 9, 2013, 07:26 AM

26. I believe its instantaneous

its speed cannot be measured.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to DCBob (Reply #26)

Sat Mar 9, 2013, 03:55 PM

31. And I believe it is not instantaneous

And my reason is very simplistic, and you may judge for yourself it is a valid argument or not, but I believe it is. Here goes, if it is instantaneous that implies perfection, and nothing is perfect and so the state of instantaneous response is unobtainable.

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Sat Mar 9, 2013, 07:26 AM

27. Far out, but not out of sight

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Sat Mar 9, 2013, 08:16 AM

28. Argh! This makes my head hurt!

 

To paraphrase my favorite green-skinned anti-hero, "Hulk smash stupid spooky action!!"

Reply to this post

Back to top Alert abuse Link here Permalink


Response to The Straight Story (Original post)

Sat Mar 9, 2013, 03:57 PM

32. Actually, it's more like they FAILED to measure the speed. nt.

Reply to this post

Back to top Alert abuse Link here Permalink

Reply to this thread