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Fluid Tests Hint at Concrete Quantum Reality

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Re: Fluid Tests Hint at Concrete Quantum Reality

#41

Post by trhway »

gohrt wrote: post #40
trhway wrote: post #9

Earlier quoted context omitted.

In interpretation of dual slit experiment people do the main mistake of mixing up the 2 waves - one is wave like quantization of position and another is de Broglie wave-equivalent of the particle. The mix up is caused by photon where both have the same wavelength. They are different in the case of all other particles. Hitachi experiment shows its the best - it clearly shows interference of the positional waves of dif…

What is a "Pivot Wave"? Do you mean "Pilot Wave"?

thanks, it was a mistype, i guess i see "pivot" much frequently than "pilot"

Re: Fluid Tests Hint at Concrete Quantum Reality

#42

Post by Sharlin »

acqq wrote: post #21
spacehome wrote: post #18

Yes! But the best theory is not Copenhagen or Pilot Wave. Eliezer Yudkowski has a brilliant treatise on the Many Worlds interpretation here: http://lesswrong.com/lw/r5/the_quantum_physics_sequence/ that really should be required reading for anyone that wants to talk intelligently on the subject. Edit: seriously, don't even bother reading the article. It (like most science journalism) is garbage. Take the time to work…

So please explain in a few sentences what is that that Yudkowski writes, did he make any new contribution to the standard model or made something else or do you agree that the standard model is the most researched and most usable model up to now, and he just made a lot of posts where he just writes a lot of text? I see a lot of links in the article you gave, but I don't understand what we're supposed to discover in Y…

The Standard Model does not concern itself with the various interpretations of quantum mechanics. It can, as of now, neither verify or falsify any of the interpretations which, consequently, are not scientific theories or even hypotheses, but firmly on the side of philosophy of physics. The interpretations are attempts to answer why Nature works as it does, within the framework of the Standard Model which only appears to answer the question how.

Yudkowsky certainly hasn't invented the many worlds interpretation, which was originally formulated by the physicist Hugh Everett in 1957. Even though originally scorned, in the more recent times it has gained popularity among physicists. The series of blog posts by Yudkowsky are (in my opinion, at least) a persuasive argument in its favor against the competing interpretations, and are very much recommended reading for anyone who would like to better understand the issue.

Re: Fluid Tests Hint at Concrete Quantum Reality

#43

Post by [deleted] »

gohrt wrote: post #39
acqq wrote: post #21

Earlier quoted context omitted.

So please explain in a few sentences what is that that Yudkowski writes, did he make any new contribution to the standard model or made something else or do you agree that the standard model is the most researched and most usable model up to now, and he just made a lot of posts where he just writes a lot of text? I see a lot of links in the article you gave, but I don't understand what we're supposed to discover in Y…

The Standard Model is a model, not an interpretation. Whether Yudkowsky is right or wrong, anyone's interpretation is going to be text, not physics.

[deleted]

Re: Fluid Tests Hint at Concrete Quantum Reality

#44

Post by acqq »

Sharlin wrote: post #42
acqq wrote: post #21

Earlier quoted context omitted.

So please explain in a few sentences what is that that Yudkowski writes, did he make any new contribution to the standard model or made something else or do you agree that the standard model is the most researched and most usable model up to now, and he just made a lot of posts where he just writes a lot of text? I see a lot of links in the article you gave, but I don't understand what we're supposed to discover in Y…

The Standard Model does not concern itself with the various interpretations of quantum mechanics. It can, as of now, neither verify or falsify any of the interpretations which, consequently, are not scientific theories or even hypotheses, but firmly on the side of philosophy of physics. The interpretations are attempts to answer why Nature works as it does, within the framework of the Standard Model which only appear…

> the interpretations which, consequently, are not scientific theories or even hypotheses, but firmly on the side of philosophy of physics.

Thanks, that's exactly what I wanted to know.

I'm completely satisfied with the "shut up and calculate" approach. For me, until somebody shows that he/she can calculate (that is, predict) more than what physicists achieve, they are the ones the closest to "the truth" and not the "interpreter."

Re: Fluid Tests Hint at Concrete Quantum Reality

#45

Post by Jach »

acqq wrote: post #21
spacehome wrote: post #18

Yes! But the best theory is not Copenhagen or Pilot Wave. Eliezer Yudkowski has a brilliant treatise on the Many Worlds interpretation here: http://lesswrong.com/lw/r5/the_quantum_physics_sequence/ that really should be required reading for anyone that wants to talk intelligently on the subject. Edit: seriously, don't even bother reading the article. It (like most science journalism) is garbage. Take the time to work…

So please explain in a few sentences what is that that Yudkowski writes, did he make any new contribution to the standard model or made something else or do you agree that the standard model is the most researched and most usable model up to now, and he just made a lot of posts where he just writes a lot of text? I see a lot of links in the article you gave, but I don't understand what we're supposed to discover in Y…

Have you read Feynman's QED? It's a bit like that, in that it's meant for a layman, but with more algebra. Instead of abstract arrows, EY goes straight to complex numbers. It goes through a basic approach to quantum mechanics (taking diagrams from here for instance: http://www.qi.damtp.cam.ac.uk/node/60) in a modern way and tries to build an intuitive understanding of the subject, especially demolishing a lot of confusions one may have gained through popular media. He then departs from the basic theory to elaborate on why the collapse interpretation is ridiculous and why Many-Worlds makes more sense. You can stop when you get to the Timeless stuff.

You're not really going to find anything ground-breaking, but it may help your intuitions about QM even if you're a physicist. As a chapter from the Aaronson book (http://www.scottaaronson.com/democritus/lec9.html) I linked to in a cousin comment says in the first two paragraphs:

There are two ways to teach quantum mechanics. The first way -- which for most physicists today is still the only way -- follows the historical order in which the ideas were discovered. So, you start with classical mechanics and electrodynamics, solving lots of grueling differential equations at every step. Then you learn about the "blackbody paradox" and various strange experimental results, and the great crisis these things posed for physics. Next you learn a complicated patchwork of ideas that physicists invented between 1900 and 1926 to try to make the crisis go away. Then, if you're lucky, after years of study you finally get around to the central conceptual point: that nature is described not by probabilities (which are always nonnegative), but by numbers called amplitudes that can be positive, negative, or even complex.

Today, in the quantum information age, the fact that all the physicists had to learn quantum this way seems increasingly humorous. For example, I've had experts in quantum field theory -- people who've spent years calculating path integrals of mind-boggling complexity -- ask me to explain the Bell inequality to them. That's like Andrew Wiles asking me to explain the Pythagorean Theorem.

(And on EY himself, just read the million or so words of the Sequences and you'll see he is actually really smart across multiple domains. ;))

Re: Fluid Tests Hint at Concrete Quantum Reality

#46

Post by GregBuchholz »

cabinpark wrote: post #17
abdullahkhalids wrote: post #11

Earlier quoted context omitted.

You are misrepresenting physicists. There have been many many different attempts to talk about quantum theory on an ontological level. Case in point, the widely debated interpretations: copenhagen, many worlds, bohemian etc. However, one reason that physicists don't spend too much time thinking about what quantum theory really means (besides laziness and bad science) is because we know that quantum theory is not the…

I agree and disagree with what you're saying. I agree it is laziness and bad science that physicists stopped caring about the philosophical underpinnings of quantum mechanics but I disagree that it was because quantum mechanics not being the ultimate theory. The reason most physicists don't think about the philosophical underpinnings has more to do with the way quantum mechanics is taught. Many of the founders were i…

>Plus, how do we rectify it with Bell's theorem on hidden variables?

I'm not a physicist, but I've always wondered about Caroline Thompson's work, like:

"Chaotic Ball" model, local realism and the Bell test loopholes

http://arxiv.org/abs/quant-ph/0210150

Re: Fluid Tests Hint at Concrete Quantum Reality

#47

Post by sedachv »

GregBuchholz wrote: post #4

I've liked: Clearing up Mysteries - The Original Goal http://bayes.wustl.edu/etj/articles/cmystery.pdf " ...we must keep in mind that Einstein's thinking is always on the ontological level; the purpose of the EPR argument was to show that the QM state vector cannot be a representation of the "real physical situation" of a system. Bohr had never claimed that it was, although his strange way of expressing himself often…

My favorite quote on the topic is from chapter 10 of Jaynes' Probability Theory: (http://omega.albany.edu:8008/ETJ-PS/cc10i.ps)

"Biologists have a mechanistic picture of the world because, being trained to believe in causes, they continue to search for them and find them. Quantum physicists have only probability laws because for two generations we have been indoctrinated not to believe in causes - and so we have stopped looking for them. Indeed, any attempt to search for the causes of microphenomena is met with scorn and a charge of professional incompetence and "obsolete mechanistic materialism." Therefore, to explain the indeterminacy in current quantum theory we need not suppose there is any indeterminacy in Nature; the mental attitude of quantum physicists is already sufficient to guarantee it."

Re: Fluid Tests Hint at Concrete Quantum Reality

#48

Post by GregBuchholz »

abdullahkhalids wrote: post #11
GregBuchholz wrote: post #4

I've liked: Clearing up Mysteries - The Original Goal http://bayes.wustl.edu/etj/articles/cmystery.pdf " ...we must keep in mind that Einstein's thinking is always on the ontological level; the purpose of the EPR argument was to show that the QM state vector cannot be a representation of the "real physical situation" of a system. Bohr had never claimed that it was, although his strange way of expressing himself often…

You are misrepresenting physicists. There have been many many different attempts to talk about quantum theory on an ontological level. Case in point, the widely debated interpretations: copenhagen, many worlds, bohemian etc. However, one reason that physicists don't spend too much time thinking about what quantum theory really means (besides laziness and bad science) is because we know that quantum theory is not the…

>You are misrepresenting physicists.

Small correction. Except for the first two lines of the parent post, the rest is a quote from Jaynes' paper linked above. It may be hard to tell because of the limited formatting options on HN.

Re: Fluid Tests Hint at Concrete Quantum Reality

#49

Post by scott_s »

acqq wrote: post #44
Sharlin wrote: post #42

Earlier quoted context omitted.

The Standard Model does not concern itself with the various interpretations of quantum mechanics. It can, as of now, neither verify or falsify any of the interpretations which, consequently, are not scientific theories or even hypotheses, but firmly on the side of philosophy of physics. The interpretations are attempts to answer why Nature works as it does, within the framework of the Standard Model which only appear…

> the interpretations which, consequently, are not scientific theories or even hypotheses, but firmly on the side of philosophy of physics. Thanks, that's exactly what I wanted to know. I'm completely satisfied with the "shut up and calculate" approach. For me, until somebody shows that he/she can calculate (that is, predict) more than what physicists achieve, they are the ones the closest to "the truth" and not the…

Last week, I wrote a comment replying to someone asking, if we can't use experiments to determine which interpretation is better, what's the point? Rather than repeat myself, I'll just link to it: https://news.ycombinator.com/item?id=7940647

Re: Fluid Tests Hint at Concrete Quantum Reality

#50

Post by acqq »

Jach wrote: post #45
acqq wrote: post #21

Earlier quoted context omitted.

So please explain in a few sentences what is that that Yudkowski writes, did he make any new contribution to the standard model or made something else or do you agree that the standard model is the most researched and most usable model up to now, and he just made a lot of posts where he just writes a lot of text? I see a lot of links in the article you gave, but I don't understand what we're supposed to discover in Y…

Have you read Feynman's QED? It's a bit like that, in that it's meant for a layman, but with more algebra. Instead of abstract arrows, EY goes straight to complex numbers. It goes through a basic approach to quantum mechanics (taking diagrams from here for instance: http://www.qi.damtp.cam.ac.uk/node/60 ) in a modern way and tries to build an intuitive understanding of the subject, especially demolishing a lot of con…

I never claimed that EY isn't smart, only that what he writes is not actually physics.

As much as I remember Feynman's lectures, he introduced the amplitudes very early?

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