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Fluid Tests Hint at Concrete Quantum Reality

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Re: Fluid Tests Hint at Concrete Quantum Reality

#51

Post by danbruc »

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…

IMHO the many worlds interpretation is one of the least appealing interpretation - millions of millions of millions of universes for nothing. What do you think about the following similar argument? Why are the laws of physics and the physical constants the way they are? There is a universe for every possible set of laws and constants and our universe just happens to be compatible with life. You can just render almost every interesting question moot with similar arguments - I would really prefer something more interesting at the heart of the universe.

Re: Fluid Tests Hint at Concrete Quantum Reality

#52

Post by acqq »

scott_s wrote: post #49
acqq wrote: post #44

Earlier quoted context omitted.

> 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

You say there: "How they lean will influence what sort of questions they investigate, how they investigate it, and what sort of outcomes they will look for."

If I understand you, we can expect that somebody is maybe going to be the first to discover something new thanks to the way he's used to think about the subject. Still, before that happens, what do we have?

Edit: Only real hard science. The discoverer we expect of course must decide from which side to attack the matter to reach the new discoveries.

Re: Fluid Tests Hint at Concrete Quantum Reality

#53

Post by Jach »

acqq wrote: post #50
Jach wrote: post #45

Earlier quoted context omitted.

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?

Fair enough. I agree a large part of it isn't strictly physics, though I think in the beginning it's like the first couple weeks of a high school Mechanics class. Low on math, but you get to do or hear about experiments and how they ought to shape your view of what's going on. (Thinking of masses and acceleration and forces, thinking of complex amplitudes and decoherence.)

Re: Fluid Tests Hint at Concrete Quantum Reality

#54

Post by jostylr »

thedufer wrote: post #25
MichaelAO wrote: post #12

FAQ about Bohmian Mechanics (it's very accessible): http://www.mathematik.uni-muenchen.de/~bohmmech/BohmHome/fil...

Its certainly accessible, but I'm not sure how much I trust the authors to understand what they're talking about after point 3. > But very often the conclusion that is drawn from this observation is that our _knowledge_ about the path followed by the electron causes the interference pattern to disappear. Although we couch the idea in terms of "knowledge", the usual meaning of that word is not what anyone thinks is ac…

That FAQ is generated by the students of a very trustworthy group. Students typically setup strawman when explaining things. Look more to the source. Also, they are trying to argue against a theory which no one wants to fully specify. So they have to come up with something definite. And as soon as they do, the other side says "Strawman!" And then proceeds, as you have just done, to refuse to give a definite theory.

As a student of that group as well, I can't say that I am all that pleased by that kind of argument.

The bottom line is that collapse is untenable. There is no good place to put it and yet it is needed by the standard theory.

Re: Fluid Tests Hint at Concrete Quantum Reality

#55

Post by acqq »

danbruc wrote: post #51
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…

IMHO the many worlds interpretation is one of the least appealing interpretation - millions of millions of millions of universes for nothing. What do you think about the following similar argument? Why are the laws of physics and the physical constants the way they are? There is a universe for every possible set of laws and constants and our universe just happens to be compatible with life. You can just render almost…

On that level I don't have any problem with "many worlds" as it can be seen just a one more extrapolation of "we're not in the designed special position" principle: first we're not the center around which the planets circle, then our Sun also isn't the center of our set of stars, then our set of stars is one of many other galaxies... if our physical universe is just a lucky variant of other possible (and mostly uninteresting) universes, it at least doesn't appear surprising.

Re: Fluid Tests Hint at Concrete Quantum Reality

#56

Post by danbruc »

thedufer wrote: post #22
cabinpark wrote: post #17

Earlier quoted context omitted.

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…

My understanding is that the pilot wave theory is a non-local hidden variable theory, which doesn't contradict Bell's theorem at all. Of course, this presents ftl information transfer, presumed to be impossible, which is part of the reason such theories have been unpopular for so long.

Non-locality does not imply the possibility of FTL information transfer - a theory can be non-local but make exploiting the non-locality impossible.

Re: Fluid Tests Hint at Concrete Quantum Reality

#57

Post by scott_s »

acqq wrote: post #52
scott_s wrote: post #49

Earlier quoted context omitted.

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

You say there: "How they lean will influence what sort of questions they investigate, how they investigate it, and what sort of outcomes they will look for." If I understand you, we can expect that somebody is maybe going to be the first to discover something new thanks to the way he's used to think about the subject. Still, before that happens, what do we have? Edit: Only real hard science. The discoverer we expect…

I don't know, but I'm not sure what you're asking. Kuhn's point (and mine, by transitivity) is that scientists are human with unavoidable biases, and these biases will influence what work they do.

The reason I don't know how to answer your question is that I interpret it to mean: what tangible result do we have before we have our first tangible result?

Of course, if that's not what you mean, then please clarify. You may want to read his book, though, as this concept is central to some of it. If you're saying, "what is the effect of such paradigms before they change," then it's best to read his book. One point he makes is that everyone operates under a paradigm, whether conscious of it or not. That is, we must think about our scientific work in some way, and whatever way we think about it will influence what scientific work we do. It is generally the case, though, that many people have some form of agreement on that "some way." When we do, that sets informal bounds on what is "acceptable science."

He does use quantum mechanics as an example, but that's loaded because we're still hashing it out. Another example he uses is phlogiston chemistry (http://en.wikipedia.org/wiki/Phlogiston_theory), which has thoroughly been supplanted. Those who first encountered oxygen were unable to recognize what it was because the paradigm in which they operated didn't contain the concept.

Re: Fluid Tests Hint at Concrete Quantum Reality

#58

Post by jostylr »

Estragon wrote: post #6

Are there any experiments where the pilot wave theory and the Copenhagen interpretation predict different results?

In pilot wave theory, one can deduce the standard quantum formalism. Operators, collapse, and all the rest just pop right out.

So no, there is no experiment that can tell the difference. It is possible that pilot wave theory has predictions that the standard formalism is silent on. However, something that is inspired by pilot wave theory can be easily co-opted by standard approaches, e.g., Bell's theorem.

Re: Fluid Tests Hint at Concrete Quantum Reality

#59

Post by jostylr »

bitwize wrote: post #15

Interesting. Maybe this will discourage chuckleheads and ne'er-do-wells from citing "quantum physics" as the justifixation for their particular variety of woo? Probably not, but one can hope!

This brings to mind a talk by someone I saw once who talked of telling the Dalai Lama about Bohmian mechanics. The response was one of gratitude for he had always felt like standard QM was a bit nonsensical.

Re: Fluid Tests Hint at Concrete Quantum Reality

#60

Post by GregBuchholz »

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…

If you can get the same answers, with a simpler or more elegant theory, you might consider that a "better" theory. IIRC, initially the heliocentric theory of the solar system gave worse approximations of planetary positions than the highly refined epicycles of the geocentric models.
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