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Thu Feb 7, 2013, 08:22 PM

Why quantum mechanics is an “embarrassment” to science

http://www.washingtonpost.com/blogs/wonkblog/wp/2013/02/07/quantum-mechanics-is-an-embarrassment/

Back in 2011, a survey was taken of various physicists and mathematicians at a conference on “Quantum Physics and the Nature of Reality” in Austria. Thirty-three of the world’s top experts were asked to list their favorite interpretation of quantum mechanics.

The result? Not a single one of the interpretations could even garner a simple majority vote. Ninety years after the theory was first developed, there’s still no consensus on what quantum physics actually means. “I’ll go out on a limb to suggest that the results of this poll should be very embarrassing to physicists,” wrote cosmologist Sean Carroll.

(On the plus side, the theory turns out to be very, very, very, very accurate in making experimental predictions. So there’s that!)

In the video below, Carroll breaks down the basics of why scientists can’t seem to agree on how to interpret quantum mechanics — and explains why it’s so critical: ”What is quantum mechanics, really? I mean, that’s like saying ‘what is the Universe?’ What more important question is there than that?”
(more)


"There are some things so serious you have to laugh at them." - Neils Bohr

42 replies, 4163 views

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Reply Why quantum mechanics is an “embarrassment” to science (Original post)
Bill USA Feb 2013 OP
MannyGoldstein Feb 2013 #1
longship Feb 2013 #2
Bonobo Feb 2013 #17
longship Feb 2013 #18
Fantastic Anarchist Feb 2013 #3
Lionel Mandrake Feb 2013 #19
napoleon_in_rags Feb 2013 #28
Fantastic Anarchist Feb 2013 #30
mindwalker_i Feb 2013 #4
Great Cthulhu Feb 2013 #6
mindwalker_i Feb 2013 #7
tama Feb 2013 #9
DetlefK Feb 2013 #10
Lionel Mandrake Feb 2013 #20
mindwalker_i Feb 2013 #21
Lionel Mandrake Feb 2013 #22
mindwalker_i Feb 2013 #23
Lionel Mandrake Feb 2013 #24
mindwalker_i Feb 2013 #25
GDNordley Jun 25 #39
mindwalker_i Jun 25 #40
napoleon_in_rags Feb 2013 #29
mindwalker_i Feb 2013 #31
napoleon_in_rags Feb 2013 #32
mindwalker_i Feb 2013 #33
napoleon_in_rags Feb 2013 #34
mindwalker_i Feb 2013 #35
napoleon_in_rags Feb 2013 #36
mindwalker_i Feb 2013 #38
stopbush Feb 2013 #5
TM99 Feb 2013 #8
phantom power Feb 2013 #11
phantom power Feb 2013 #12
Great Cthulhu Feb 2013 #13
phantom power Feb 2013 #14
dimbear Feb 2013 #15
Bill USA Feb 2013 #16
Duppers Jun 26 #41
leveymg Feb 2013 #26
pangaia Feb 2013 #27
DreamGypsy Feb 2013 #37
Duppers Jun 26 #42

Response to Bill USA (Original post)

Thu Feb 7, 2013, 08:51 PM

1. Same as it ever was:

I think I can safely say that nobody understands quantum mechanics.
Richard Feynman, in The Character of Physical Law (1965)

And he got a Nobel Prize for work in.. quantum mechanics!

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Response to MannyGoldstein (Reply #1)

Thu Feb 7, 2013, 09:08 PM

2. Actually, it was quantum field theory.

But maybe that's a distinction without a difference.

QFT takes the mechanics I learned in undergrad physics quite a bit further than particles tunneling through potential wells and the evolution of probability waves, etc. we studied in junior year.

I like Sean Carroll a lot. And although I don't have bandwidth for video right now, I can imagine what he says in it.

I responded so I could blab on and also support the thread. I'll stop blabbing now.

R&K

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Response to longship (Reply #2)

Sat Feb 16, 2013, 03:41 AM

17. I thought it was quantum electro-dynamics. nt

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Response to Bonobo (Reply #17)

Sat Feb 16, 2013, 05:24 AM

18. QED is a Quantum Field Theory.

As is quantum chromodynamics. As is the electroweak theory.

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Response to Bill USA (Original post)

Thu Feb 7, 2013, 10:12 PM

3. I favor the "Many Worlds" interpretation of Quantum Mechanics myself.

But, I guess that's why I'm not a physicist.

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Response to Fantastic Anarchist (Reply #3)

Sat Feb 16, 2013, 01:25 PM

19. So does Murray Gell-Mann,

who won a Nobel Prize in physics in 1969. So you're in good company.

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Response to Fantastic Anarchist (Reply #3)

Sun Feb 17, 2013, 03:54 AM

28. Check out the Zero Worlds theory:



Its from one of the guys that contributed hugely to Google. The gist is you discard the idea of this underlying universe which we are observing, and you embrace the observations themselves as the fundamental reality. It feels a little like The Matrix, but does make sense.

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Response to napoleon_in_rags (Reply #28)

Sun Feb 17, 2013, 03:05 PM

30. Thanks, I'll check it out.

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Response to Bill USA (Original post)

Thu Feb 7, 2013, 10:14 PM

4. Fuck the Copenhagen Interpretation

"Shut up and calculate" just doesn't wash with me. The basis behind it is that the wave function just represents what we can know about a system, not the reality of that system. It's like saying that when you roll a die, the probability of it landing on any number is a measure of how much you know about it or don't, so the wave function is just how much you know or can know about an event coming out a certain way. The problem is that those possibilities interfere with each other - see the double-slit experiment.

For entanglement, Einstein claimed that the entangled particles really did have states before measurement, we just didn't have a theory that would allow us to know those states beforehand. Bell's theorem kicked that ass. There's also a similar theorem about the wave function. If it only represents lack of knowledge, then it can't predict the results of QM and experiment.

Here's the deal: we don't understand the reality below the universe. What was there before the big bang? No universe, no space, probably no time (which makes it logically difficult to talk about "before" the big bang). Then the big bang happened, space and time came out of that expansion of "stuff," and here we are, but the universe would still be encompassed within that lack of space - what exists that is not the universe.

Einstein said nothing can go faster than light. But he was dealing with things in the normal, classical universe. Quantum goes below that and, I believe, isn't limited to the same rules as the classical universe. Quantum effects can violate light speed and I bet they can violate causality as well (kind of implied if they violate light speed). See here:

http://quantizedimagination.wordpress.com/entanglement-and-retrocausal-signaling/

None of the interpretations of QM deal with this. I don't think we have enough information to even formulate a theory of the under-the-universe bit yet, so I'm not surprised that no one agrees on an interpretation yet.

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Response to mindwalker_i (Reply #4)

Thu Feb 7, 2013, 11:17 PM

6. to be fair to Einstein

 

He said C was the speed limit in the Universe. The Universe itself can (and seems to, in some scenarios) expand faster than C, and this is completely in line with Relativity.

Yes he was spooked by Entanglement, but the implication is that Information is traveling faster than C within the Universe. So far, no one has been able to prove that Information is being moved between entangled particles at all (which I think is just freakin' cool, personally).

I find Entanglement to be at least as weird as the Double Slit experiment, but both are fascinating as hell.

Not gravitons, though. There I call BS until someone can 1) catch one and show it to me, and 2) explain how it can blitz past an Event Horizin while a photon can't.

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Response to Great Cthulhu (Reply #6)

Thu Feb 7, 2013, 11:28 PM

7. From the article I linked

In 1998 Birgit Dopfer measured entangled photons with those going through a double-slit, and when she did, the interference pattern disappeared. This has also been done where the entangled beam is measured AFTER the original beam has created interference or not. I've read some things that say it isn't really making cause follow effect, but those arguments don't make sense to me yet.

Quantum mechanics will rip your brain out of your skull, wring it out like a sponge and stick a withered, mummified version back in your head. Once you get over that, it's pretty cool

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Response to mindwalker_i (Reply #7)

Fri Feb 8, 2013, 04:43 AM

9. Delayed choice

 

http://en.wikipedia.org/wiki/Wheeler's_delayed_choice_experiment

Wheeler's "participatory" universe and delayed choice suggests that each measurement event creates both "past and future", ie. 4D space-time geometry as whole (including classical causality) evolves and is replaced with another 4D space-time geometry in each measurement. But to make nature more sticky (and stick together, unlike many-worlds), it seems this view needs to be accompanied with some sort of Russian doll hierarchy of space-time geometries within space-time geometries.

The astronomical experiment, if and when done succesfully, should also solve the scale problem.

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Response to mindwalker_i (Reply #4)

Fri Feb 8, 2013, 07:24 AM

10. Agreed. The wave-function isn't the system itself.

It's not a physical observable in itself. And it's only related to probability density as long as we stay on the non-relativistic side of QM.

The wave-function is a mathematical tool with which we can get physical information on said system by way of operators and eigenstates 'n stuff.

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Response to mindwalker_i (Reply #4)

Sat Feb 16, 2013, 01:35 PM

20. You are mistaken.

Quantum mechanics, including quantum field theory, is causal and never allows a particle or information to travel faster than light.

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Response to Lionel Mandrake (Reply #20)

Sat Feb 16, 2013, 08:42 PM

21. That's what a lot of people think

Dr. John Cramer is trying to prove them wrong using entanglement. Actually, entanglement does send information faster than light, obviously, but many people believe that we (humans) can't use it to send useful information. I think there's good reason to believe it's possible.

What you did above is make a statement without backing it up with any information or reasons. I could accept you saying something like, "there are proofs that entanglement can't be used to send useful information," or you could have quoted relativity. Then we could have had an interesting discussion on either of those statements. Unfortunately you leave no basis for me to argue against, and therefore I can only assume certain arguments, or dismiss you with no explanation.

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Response to mindwalker_i (Reply #21)

Sat Feb 16, 2013, 10:37 PM

22. Okay, let me rephrase that.

There is a broad consensus among theoretical physicists that information can not travel faster than light.

I know it's possible to entangle to objects (e.g., electrons) and move them far apart. Formally, a measurement of one of them changes the state of the other. But there seems to be no way to extract information that would tell you the result of the distant measurement.

If information could be transmitted instantaneously over a considerable distance in one frame of reference, then it could be transmitted backward in time in another frame. That would violate causality. It would take very strong evidence to convince me of that possibility.

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Response to Lionel Mandrake (Reply #22)

Sun Feb 17, 2013, 12:15 AM

23. Ok, that's better :)

The consensus on things or information not being able to travel faster than light is based on relativity, specifically as something increases in speed, its mass also increases so it takes more and more energy to accelerate it further. Getting to light speed would therefore require infinite energy, let alone getting past light speed.

Good enough. However, with entanglement, there is "nothing" being used to send a signal. No brick, envelope, or photon is being sent between the entangled particles, so it isn't subject to special relativity. The arguments I've read that claim entanglement can't be used to send information are along these lines: Alice and Bob each receive one particle of an entangled pair. If Bob looks at his - say he tests it for polarization - he will get a random result. It will either be polarized horizontally or vertically. If Alice then measures her photon, she will get either the same or opposite result as Bob, depending on how the photons were prepared, but it will still be a random value. Thus, there is no way to distinguish between an initial random value, and a random value matching Bob.

However, there's a possible way to use this that is fundamentally different. Before either photon is measured, they are both in a state of superposition of both values. When one is measured, then neither of them are in superposition anymore. Now, when photons are in superposition, there are multiple possibilities for the value of a property one will get when they measure that property, but fundamentally, those possibilities can interfere with each other. In the double-slit experiment, the possibilities for which slit a photon goes through interfere with each other, eventually resulting in the interference pattern.

In 1998, Birgit Dopfer did an experiment where one entangled beam went through a double slit and did or did not create an interference pattern. The other beam could be measured either in such a way as to get the which-way information (momentum) or to hide the which-way information. When the momentum was measured and could, in principle, tell which way the entangled photon went through the double-slits, the interference pattern was destroyed.

What Dr. Cramer is trying to do is to first, prove that information can actually be sent this way and then if so, use it to send and detect a signal faster than light would normally allow for. If that works, he wants to delay the photons to be measured with fiber optics so there is a significant delay between detection and measurement, thus detecting or not detecting an interference pattern before the choice is made to preserve or destroy the momentum information.

So yes, most physicists might agree that information can't go faster than light, but there's reason to question it. And just because most physicists agree isn't proof. Hell, Einstein didn't buy quantum mechanics, and he was wrong.

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Response to mindwalker_i (Reply #23)

Sun Feb 17, 2013, 12:50 AM

24. "Einstein didn't buy quantum mechanics, and he was wrong."

But notice that, in this case, it was the minority view (Einstein's) that was wrong, while the majority view (in favor of QM without hidden variables) turned out to be correct.

As he grew older, Einstein gradually withdrew from the mainstream of physics. He spent his last years pursuing a peculiar vision of a unified field theory, which never led anywhere. Meanwhile a generation of physicists accepted the dictum: "Shut up and calculate", which led to success after success in solid state physics, chemistry, nuclear, and high-energy physics.

What I take away from this history is that the best way to do science is to follow the consensus until or unless that becomes completely untenable; then and only then try something radically different.

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Response to Lionel Mandrake (Reply #24)

Sun Feb 17, 2013, 01:05 AM

25. That seems like a very conservative view

I don't mean it politically, but "going along with the crowd" until one simply can't doesn't sound like a good way to make discoveries. Not too long ago, I was talking to Gerald Nordley. He's a physicist and author of science fiction, and I got the distinct impression that he disagreed with the normal interpretations of QM in favor of a much more classical view. For example, he pointed me to an article that attempted to refute Bell's theorem, but more than that, it seemed like he didn't want to believe that entanglement was actually happening.

So, at least for some people, they take a "conservative" view of physics that kind of tries to sweep the more interesting and weird things that we see under the rug. The Copenhagen Interpretation is a very wide-spread example. It says not to even ask the questions about the underlying reality. It definitely has led to a lot of correct predictions and results, but it has also held us back, a lot. Copenhagen almost sounds like religion in that it says "here's how stuff is, don't question it."

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Response to mindwalker_i (Reply #25)

Wed Jun 25, 2014, 06:09 PM

39. That seems like a very conservative view

Greetings, mindwalker.

I seem to have stepped in it. I don't remember the conversation or the article and possibly miss spoke. There's no question in my mind that entanglement, at least in the sense of a persistent correlation of separated quantum pairs, actually happens; that's been pretty well observed. But there is controversy on whether one can actually transmit causal information "instantly" (in what frame of reference?) by "observing" distant entangled particles. Bell's inequality seems a solid enough predictor of statistical measurements, as far as I know, but there are interpretation issues (possible the subject of the article?) and a number of hoops to go through before using that to justify FTL or time-reversed communications. I would rather leave that discussion to experts in the field, like John Cramer. (I find John's "transactional" interpretation attractive from a number of respects, but I'm not sure I would call that "conservative"!)

What I AM very confident of is that FTL by any means is time travel (one only needs algebra to demonstrate that). The mathematical representation of that is the Lorentz transformation. GPS, deep space communications, and so on depend on it. The readings of "clocks" at distant locations are predicted by the transformation equations, and have proved very accurate over a very wide range of relative velocities with a wide range of relative velocities, observations and measurement techniques. This is called "Lorentz invariance" and is a hard-won empirical law of nature, not a theoretical construct. (Einstein showed one could derive the equations from the observation that the speed of light is the same when measured in any frame of reference, but the empirical equations already existed; hence it isn't called the Einstein transformation.) Lorentz invariance is logically inconsistent with an absolute time reference; i.e., the same event would have to have different time coordinates.

--Best, Gerald

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Response to GDNordley (Reply #39)

Wed Jun 25, 2014, 10:52 PM

40. Sir! Welcome to DU

You must have Googled yourself and found this message from over a year ago, then logged in and gotten an account. Good to see you!

We spoke at BayCon - not the latest, but a year or two before. It's my impression that many physicists try to avoid the odd aspects of QM like entanglement and try to explain those more in classical terms. Copenhagen seems very much like a thin excuse to avoid thinking about the implications of QM. Of course, that may just be in comparison to my eagerness to find the weirdest stuff out there and believe it.

I actually started building Cramer's experiment about a year ago. I've had a certain amount of success making a Mach-Zehnder interferometer and have gotten decent interference patterns from it. By placing some simple three-terminal light sensors that look like transistors after galvanometer sets, I could scan out the intensity onto an oscilloscope. Cats walking by destroyed those scans. Now, I'm working on optic mounts to allow adjustment in X and Z directions, diagonal, rotation, and tilt.

I also have a pair of single-photon detectors and a BBO crystal, although I haven't worked with them much yet. I'll get there.

Anyway, about this whole idea of transmitting information through entanglement: the experiment relies not on the individual state of each photon, but on the states of many photons to be either left in superposition in terms of their momentum or collapsed. The Mach-Zehnder interferometer acts like a double-slit that doesn't lost 99.99% of the photons to hitting a wall, and detects whether their momentums are in superposition. If the entangled photons are measured - collapsed - the interference pattern will be degraded (20-30% of the photons should be entangled, and only those will have their momentum collapsed). Logically, it makes sense that this will work to transmit a binary value, continuously. In contrast, what I understand about the arguments that entanglement can't be used to send information rely on the using single photons. If one reads momentum (or polarization), they get a random value from the possible values. The other person gets a complimentary value, but it's the complement of a random value.

In this case, it should be possible to detect the change in whether the photons are in superposition after a number of them have been detected and found to be mostly in the places where the interference pattern would be bright, or not. If a Mach-Zehnder interferometer is tuned just right, all the photons should go out one "port" of the final beam splitter - none on the other port, so if some do come out the other port, that indicates momentum is being measured on the entangled partners.

From relativity, this becomes a time machine, assuming that the effect is faster than light. But one doesn't even need relativity. The measurement of the entangled partners can be done after the photons going into the interferometer have already been detected, similar to the delayed choice quantum eraser. I don't really understand the arguments as to why that experiment transmitting information or isn't retrocausal, so I can't do a decent job of arguing against it. Will Cramer's experiment work? I'm not sure, but if it doesn't, I imagine we could find ourselves in a situation where uncertainty is violated - or we both know which "slit" a photon went through and also get interference. Something's gotta break.

Possibly, this will end up as a tool to probe time, or at least probe the logic underlying the quantum universe. I've got this feeling that there was a Big Bang, but before that (as much as "before" can even be defined prior to the Big Bang), the was no universe and no time. QM might be showing some of the physics that operate on whatever this not-a-universe was, and therefore wouldn't be subject to the regular limits of locality and causality. This hypothesis lacks a huge amount of supporting data, admittedly, but it's a starting point that allows me not to get stuck trying to reconcile experimental results with what I think should happen.

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Response to mindwalker_i (Reply #23)

Sun Feb 17, 2013, 04:13 AM

29. There's some remarkable stuff sleeping behind the "no information sent faster than light" business.

The main one is Quantum Teleportation. By metaphor:

Alice has a black box with two coins inside, Bob has an (entangled) black box with two coins in it. Each black box has two led lights on the top.

Alice sets her two coins to the two bits she wishes to send bob, and closes the box. (breaking the entanglement in altering them) The two lights light up in a way totally uncorrelated with what she just did. she sends the result of the two lights to Bob, using a normal slower than light communication channel.

Bob opens his black box, and finds his coins in an arbitrary state. He flips those coins based on the received information about Alice's two lights. The result is Alice's two-bit message.

If you stand back and look at that, it makes a remarkable statement about this universe: Its possible to send a message, to send information, which is in no way correlated with the actual information sent. Sit back and really chew on that line. In a world with radio waves pulsing through our brains at all times from satellites, radio towers and the rest, the possibilities that simple fact presents us with, accidental and intentional are really remarkable.

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Response to napoleon_in_rags (Reply #29)

Sun Feb 17, 2013, 05:05 PM

31. Now that's interesting

I haven't paid that much attention to teleportation since it still relied on sending some information classically. However, from your description, there's something fundamentally weird and therefore interesting going on, so I'll read up on it!

That's what I'm getting at here: the experiments are telling us that the universe has some fundamental qualities that are very contrary to what we expect, and there's also a good possibility that some of these things will be very useful in some way or another. Cloaking all of QM behind "shut up and calculate" robs of of exploring those possibilities.

I was thinking about Birgit Dopfer and Dr. Cramer this morning while taking a shower, and it occurred that possibly, I could sort of redo Dopfer's experiment but using photons that had entangled spin as opposed to momentum. In the original, one beam was sent through a double slit and the other beam was sent to a lens. The double-slit beam would form an interference pattern unless the lens beam was sent to a detector in such a way as to preserve the momentum, thus allowing, in principle, for the which-way information to be obtained.

I'm thinking that a variation would send one beam into a certain type of interferometer instead of a double slit. The interferometer would normally have a beam hit a half-silvered mirror to split it into two beams that would go to two full mirrors that would reflect each sub-beam back to the same place. Where they intersected again, another half mirror would recombine them. This also generates an interference pattern. However, instead of a half-silvered mirror in the first part, I would use a mirror that reflects photons based on their polarization. The sub-beams would reflect again back to the final recombination and interfere with each other. If, however, the which-way information was obtained from the entangled beam by splitting that based on the entangled photons' polarization and NOT recombined, it should destroy the interference pattern on the original interferometer.

Here's a diagram of the interferometer (can't seem to get it to embed in this post):

http://physics.aps.org/articles/large_image/f1/10.1103/Physics.4.102

Dopfer's original experiment used a "coincidence detector" to filter out non-entangled photons and I might need to do the same, depending on what percentage of photons are entangled. what I'm hoping is that a high enough percentage are entangled that by saving the which-way information on just the entangled photons will produce enough of a changed in the interference pattern to be detected.

Also, the original experiment use a crystal of beta barium borate (BBO) pumped by an ultraviolet laser of 351.1nm. I don't have such a laser, but 405nm laser diodes are readily available and a hell of a lot cheaper. BBO crystals are about 500 bucks.

There are a lot of technical and economic challenges to building this, but if I could do it without a coincidence detector, it would demonstrate using entanglement to send information. If it didn't work, the method of failure could also provide very useful information.

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Response to mindwalker_i (Reply #31)

Sun Feb 17, 2013, 06:58 PM

32. Go for it! And post on DU.

I have no idea what would happen in this experiment. I have heard its been proven impossible to send information, so setting it up looking for that useful information in the method of failure might be the best way. But its only what I heard, I have a pretty voyeuristic relationship with QM, I don't have a big background in physics, but I read what I can.

You know what we need though, seriously? Web labs. Chemistry, optics, physics labs with web interfaces. We can have them do whatever experiment we want for $20 /hour. With all the pieces they could knock this thing out so fast, and so much cheaper than you have to put all that money down.

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Response to napoleon_in_rags (Reply #32)

Sun Feb 17, 2013, 08:45 PM

33. Dr. Cramer addressed the no-information theorems

He noted that at least some of them are tautological - the result is (subtly) build into the assumptions made. He is trying to test the retrocausal aspects (effect preceding cause) with an experiment that my idea is based off of. But I just want to check whether information can be sent through entanglement. He has a specific type of crystal that should produce a whole lot more entangled pairs, but it's extremely sensitive to wavelength, so he want to tune that by keeping the temperature constant at 40C. Apparently that should keep the wavelength exactly at 405.0nm.

Incidentally my relation to QM is like yours. one of my majors on college was physics but I didn't get into QM - that came later when I got interested in it. Actually it's Cramer's experiment that kind of triggered a latent interest in entanglement. I met him at a sci-fi convention a few years ago, fed him a beer and picked his brain. The dude is my hero!

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Response to mindwalker_i (Reply #33)

Mon Feb 18, 2013, 12:47 AM

34. Are you talking about John G Cramer?

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Response to napoleon_in_rags (Reply #34)

Mon Feb 18, 2013, 12:58 AM

35. Yup, that's him

Hacker of the freakin' universe! - in that he's hacking the universe. He gave a presentation at Norwescon three years ago on his experiment, what difficulties he was having, and what he was doing to solve those.

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Response to mindwalker_i (Reply #35)

Mon Feb 18, 2013, 02:13 AM

36. UW is doing some amazing work.

I live in the Sound, so I watch UWTV all the time for the computer science talks. I wish they had more philosophy on physics talks, or sci-fi futurist talks... But anyway, this work caught my eye:

http://www.washington.edu/news/2012/12/10/do-we-live-in-a-computer-simulation-uw-researchers-say-idea-can-be-tested/

That's so outside the box its amazing. Cramer seems like a prime example of that culture, the more I read about him, the more he seems like an amazing guy.

But as far as the no information thing, yeah why can't information go faster than light? I heard the mass of things will increase as they approach the speed of light, but how much does a megabyte weigh?

there's different intuitive concepts of what information is. Suppose I have an LED screen on my wall that displays a number, which is always perfectly correlated with the amount of pennies in your wallet. Yet no discernible cause exists for this, no radio sensor in your wallet or anything, it just changes randomly and we just happen to live in a universe where this bizarre coincidence exists. Does not the screen on my wall have information on the money in your wallet during the period of time this coincidence continues?

That definition of information is that so long as the knowledge system (LED on the wall, my brain) has its states correlated with the thing observed, it has information on it.

Another example: On two separate ends of the expanding universe, two aliens on different planets just discovered the Fibonacci sequence. Both are calculating and writing down the sequence, so what's on alien A's pinx papyrus is perfectly correlated with what's on alien B's xargoxic writing tablet. Doesn't alien A's papyrus have information on what's on alien B's tablet since they are by definition perfectly correlated? (they both are good at math) Since they live on different sides of the universe, doesn't that mean faster than light communication? Of course not. Yet an observer could predict the next value on the tablet from knowing the next value on the papyrus.

Now contrast that with you DON'T have the name of an author, can't get it, and I send it to your phone. Here I have physically effected a state change on your phone's hardware, to get the information to you. This obviously had a physical cause that moves slower than light. That's a different type of information, as it needs a physical state change rather than a pre-existing or spontaneously arising correlation.

So does correlation exist all over the universe? Obviously, yes, or there wouldn't be laws of science. But how deep does that go? In the first example, we had a thing, an information entity, the Fibonacci numbers, basically existing in two places at once, and correlating the actions of two distant aliens. What else can do that? An idea? An emotion? Common laws of physics? Who knows. Its just that this phenomenon may go way deeper than it appears. So in a sci-fi setting, two astronauts wouldn't communicate (which is to say create physical state changes) non-locally, it would simply be that the knowledge system, their mind(s) would be in two places at once, like the Fibonacci numbers were for the aliens, so the minds of the astronauts were correlated, so they both saw through each others eyes. This is subtly different from astronaut a telling astronaut B something through a physical action.

Anyway, I'm getting out there. I love sci fi stuff.

PEace!


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Response to napoleon_in_rags (Reply #36)

Mon Feb 18, 2013, 01:46 PM

38. Thanks for the link!

I'll have to peruse their site and see what else they're up to.

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Response to Bill USA (Original post)

Thu Feb 7, 2013, 11:12 PM

5. Saying that science is "embarrassed" by not having a consensus on QM

imagines that there is some time limit or deadline on coming to an understanding of things scientific.

It could be hundreds of years before a consensus is reached on QM. The consensus will be reached when it is reached.

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Response to Bill USA (Original post)

Fri Feb 8, 2013, 01:52 AM

8. Exactly

Because as we all know a consensus of all scientists on board with Newtonian physics and the Copernican revolution occurred within those men's lifetime.

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Response to Bill USA (Original post)

Fri Feb 8, 2013, 10:01 AM

11. Hard for me to believe a scientist would display such a misunderstanding of science.

Oh noez, there is no consensus on topics at the frontiers of our undersanding...

wow, really? who knew?

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Response to Bill USA (Original post)

Fri Feb 8, 2013, 10:07 AM

12. and another thing

a cosmologist is throwing down about lack of consensus? A fucking cosmologist?

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Response to phantom power (Reply #12)


Response to Great Cthulhu (Reply #13)

Fri Feb 8, 2013, 03:03 PM

14. I feel totally sure it can all be properly modeled as a quantum graph automata

technically, I don't feel even a little bit sure of that, but I am totally sure it would be cool.

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Response to phantom power (Reply #12)

Fri Feb 8, 2013, 10:18 PM

15. That is a damn good point. Cosmologists with their constants that they have to

retweak every few years, often by 20% or so.

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Response to phantom power (Reply #12)

Fri Feb 15, 2013, 05:22 PM

16. I have really enjoyed reading everyone's comments to OP - All were very interesting. (but that's

... what I was hoping for)

I think the Cosmologist is uncomfortable even observing (even though, apparently, not involved in it) others efforts in scientific exploration - at the edge of our understanding of the natural world (but isn't this where it's most exciting?).

For a while our understanding may seem a bit 'ragged'. But I think in time (a couple centuries?) theoreticians and experimenters will lead us to a deeper understanding of what right now is quite confounding. This might very well involve additional dimensions than the four (relativistically speaking) we are familiar with now (which will involve increasing the powers to which the terms in our equations are raised.). Meaning the 4 dimensions we are conscious of now, may just be some nth derivative of the most fundamental level of reality. (perhaps a variant of this is the proposition that the world we are aware of is really a sortof Hologram produced from more fundamental phenomena)

My 'take' on this is why would anybody think that Nature is going to make it easy for us humans to figure out what's really going on. Some, like the cosmologist, may be lacking in the ability to tolerate ambiguity. In ambiguity lies opportunity.

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Response to Bill USA (Original post)

Sun Feb 17, 2013, 01:11 AM

26. Let's face it, technical people are uncomfortable with uncertainty. eom.

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Response to Bill USA (Original post)

Sun Feb 17, 2013, 01:53 AM

27. Can you imagine a teapartier reading this thread?



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Response to Bill USA (Original post)

Mon Feb 18, 2013, 04:09 AM

37. Yeah, yeah. Another fluffy interview with an important scientist...

...and the result is that quantum mechanics needs a fig leaf.

Did anybody here go look for/at the data?

Here's an article from the MIT Technology Review that has at least a slightly less emotional title: Poll Reveals Quantum Physicists’ Disagreement About the Nature of Reality : http://www.technologyreview.com/view/509691/poll-reveals-quantum-physicists-disagreement-about-the-nature-of-reality

First paragraph is OK:

Quantum mechanics lies at the heart of many modern technologies–lasers, superconductors, many forms of computing, cryptography and so on. That’s partly because the theory is so good and well tested to mind boggling accuracy.


Right, we wouldn't be using the devices we use to look at these articles if quantum mechanics didn't work.

Second paragraph brings in the drama and appeals to our fears:

And yet, there is trouble at the heart of quantum mechanics and the way we should use it to understand the nature of reality. Perhaps nothing reflects this better than a survey published today by Anton Zeilinger at the University of Vienna and a couple of buddies. These guys have surveyed a group of physicists, philosophers and mathematicians about their views on the foundations of quantum mechanics.


Oh my, trouble at the heart of QM.

Here's the actual paper on which the articles are based: A Snapshot of Foundational Attitudes Toward Quantum Mechanics: http://arxiv.org/pdf/1301.1069v1.pdf


1 Why this poll?
In August 1997, Max Tegmark polled 48 participants of the conference \Fundamental Problems
in Quantum Theory," held at the University of Maryland, Baltimore County, about their favorite
interpretation of quantum mechanics . By Tegmark's own admission, the survey was \highly
informal and unscientific," as \several people voted more than once, many abstained, etc." While
the Copenhagen interpretation gathered the most votes, the many-worlds interpretation turned out
to come in second, prompting Tegmark to declare a \rather striking shift in opinion compared to
the old days when the Copenhagen interpretation reigned supreme."
Today, debates about the foundations of quantum mechanics show no sign of abating. Indeed,
they have only become more lively in the years since Tegmark's poll. Thus, we felt the time had
come to take a new snapshot. A perfect photo opportunity had just presented itself: the conference
\Quantum Physics and the Nature of Reality," held in July 2011 at the International Academy
Traunkirchen, Austria, and organized by one of us (A.Z.). A mix of physicists, philosophers, and
mathematicians had gathered at a former monastery at the shore of Lake Traunsee in Austria
(see Appendix B for a list of participants). We handed the conference participants a prepared
questionnaire with 16 multiple-choice questions covering the main issues and open problems in the
foundations of quantum mechanics. We permitted multiple answers per question to be checked,
because in many cases the di fferent answers were not, and could not be, mutually exclusive.
Just as Tegmark's poll, our poll cannot claim to be representative of the communities at large.
But, as a snapshot, it contains interesting|and in parts even surprising|information. A total
of 33 people turned in their completed questionnaires; of those, 27 stated their main academic
affiliation as physics, 5 as philosophy, and 3 as mathematics (here, too, multiple answers were
allowed). While this is not a huge sample size, it is to our knowledge the most comprehensive poll
of quantum-foundational views ever conducted.1 Also, we were certainly aware of the fact that the
multiple-choice format can sometimes obliterate the all-important nuances: two people may check
the answer \local realism is untenable," and yet mean completely di fferent concepts by each word
in this sentence. This, however, is a small price to pay for the ability to directly tally up the votes
and to analyze correlations between answers.


Now we know the depth and breadth of the study. Cool. The paper presents all the questions, the choices for answers, and the distribution of responses. My personal reaction: Wow, 72% of the respondents think we'll have a working quantum computer within 10 to 50 years. Incredible! I only wish I would be around to witness it!!!

However, the conclusions of the study are rather disappointing:

5 Conclusions
Quantum theory is based on a clear mathematical apparatus, has enormous significance for the natural
sciences, enjoys phenomenal predictive success, and plays a critical role in modern technological
developments. Yet, nearly 90 years after the theory's development, there is still no consensus in the
scientifi c community regarding the interpretation of the theory's foundational building blocks. Our
poll is an urgent reminder of this peculiar situation.


Shit. We're only ninety years into the investigation of aspects of reality that totally boggle our acutely limited, fragile, and incorrect perceptions. Do we need an urgent reminder to solve this 'peculiar situation'?? No, we need to revel in our confusion, excitement, and disagreement, just hoping that a hundred...or a thousand years from now our descendants will fully agree on the aspects of the universe that trouble us now, but will still stand on the precipice of knowledge undiscovered. That's why the trip is so much fun!


(on edit: my link to the MIT article didn't work; fixed)

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Response to DreamGypsy (Reply #37)

Thu Jun 26, 2014, 03:26 AM

42. Great post!

Little quibble with a tiny part there at the last - sadly, I don't think this species will have descendants a thousand years from now.

I am hopeful that physicists will agree on most aspects within the next hundred years, that is if all funding for physics doesn't dry up under the stress of simply trying to survive the coming onslaught.


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