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Comment by the__alchemist | Hacker News Reader

I don't buy it: The point of looking for an interpretation is to find a deeper, more detailed theory, or model that explains the QM observations, and perhaps more. Here's an analogy:

> The sun and stars trace arcs in the sky. One interpretation is the earth is the center of the universe, and the sun and stars move around it. Another is the sun is at the enter, and the earth and stars move around it. I can predict where the sun will be at any time of day, and day of the year based on these observational charts. The motion of celestial bodies is what it is, and doesn't need an interpretation

The flaw here is that by understanding more deeply what's going on with this analogy, we can learn so much more about the cosmos, like explaining the motion of planets etc etc. By not seeking an interpretation of quantum mechanics' observations, we limit ourselves.

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There's no particular reason to think that an overarching interpretation of quantum mechanics will provide a deeper understanding of it compared to the strict formalism. People can come up with metaphors to assist in teaching it and there can be numerous such metaphors that are useful depending on what specific aspect is being understood.

Furthermore I don't agree that people are limiting themselves because of a lack of an interpretation, on the contrary my personal observation is that people are limited precisely because they either seek an interpretation or are clinging to one.

Why do you draw the line here, at QM, as a boundary of knowledge? This may be the case, and is a common opinion, but why is this special, compared to various other theories we have in physics and other sciences?

Historically, this line of thinking is common in science. You might be right here; science has advanced far in the last century, but I urge you to exercise skepticism that we've really hit the bottom. Nearly all claims of this type historically have been wrong!

seeking an interpretation is what leads you to the zen anti-interpretation. You learn and learn and start to understand the things you've learned weren't meaningful.

> the endpoint where you intuitively understand exactly what a Many-Worlder, Copenhagenist, or Bohmian would say about any given issue, and also how they’d respond to each other, and how they’d respond to the responses, etc. but after years of study and effort you’ve returned to the situation of the baby, who just sees the thing for what it is.

> The flaw here is that by understanding more deeply what's going on with this analogy, we can learn so much more about the cosmos, like explaining the motion of planets etc etc. By not seeking an interpretation of quantum mechanics' observations, we limit ourselves.

But the sun being the center of the universe is a physical theory. It makes testable predictions. We can learn something about the universe from such a theory. On the other hand, most of the interpretations of quantum mechanics are metaphysical theories closer to religion than science. They do not make testable predictions or allow us to learn about the cosmos. They may be interesting thought experiments but they teach us as much about quantum mechanics as debating heaven and hell teach us about death.

[IANAP]

It occurred to me while reading Scott's blog article that a very interesting idea for a SciFi novel would be to explore a future society where are current religions are replaced with these QM religions.

Reminds me - what happened to the Church of String, I mean String theory? IIRC that was the ultimate "nothing can ever be tested, not even a tiniest part" theory

This is very unfair to string theorists, who

a) are almost universally honest about the empirical difficulties in their field,

b) are reasonably exploring the possible theoretical options to hopefully create testable predictions for a future experiment/telescope (science is hard)

c) have made major advances in mathematics, with important (and testable) applications outside of string theory

I feel like you’re projecting the attitude of one sometimes unscrupulous scientist (Brian Greene) onto the entire field. Although laypeople’s fascination with string theory has died down it is still a vital and vibrant field.

For me, part of the "Zen Anti-Interpretation of QM" is to accept that there will be theories that are untestable mathematical models of reality. Testable mathematically - but not with a big particle accelerator.

> One interpretation is the earth is the center of the universe, and the sun and stars move around it. Another is the sun is at the enter

Then along comes relativity theory and says that both of these are equally right. There is no "center" and therefore when making calculations you should just pick whatever center - frame of reference, that is - makes the calculations simpler. For example, you'll have a much easier time doing the math of planetary motion if you pick the sun as your frame of reference, but you could pick the earth if you wanted to.

However, if you want to calculate the movements of stars in the Milky Way, you should no longer use the sun as your frame of reference - instead, use the center of the galaxy.

But you could, if you wanted to? At least by your analogy?

Yes, you could, in theory, although the math would probably be so complex you could never solve it.

This isn't an analogy though, it's a direct consequence of relativity theory. It's the reason the word "relativity" is in the name.

It's true that there's no universal center, and relativity supports this.

However, dropping the idea of a universal center, it's false that the Earth is the center of the solar system, i.e. the other major objects in the solar system don't revolve around the Earth, even though it's possible to produce a consistent Earth-centric model that works like that.

Relativity doesn't say that both an Earth-centric and solar-barycentric models are equally correct, since the Earth-centric model is not an inertial frame, and Earth's contribution to spacetime curvature is one of the smaller ones. Both special and general relativity allow us to draw reliable conclusions about which models better represent reality, as opposed to just making accurate predictions.

As such, this example provides better support for the idea that interpretations matter, than that they don't. It suggests that the situation with quantum interpretations may well be similar. You can make accurate predictions under any sufficiently complete interpretation, but that doesn't mean that there isn't an interpretation that's a better fit to reality than others. We may just lack the ability to determine that yet.

Aaronson's take is similar to the "shut up and calculate" take in the sense that it explicitly ignores or rejects the question here. It's an anti-knowledge position - it's saying we should be happy with what we already know, and simply work within that framework, ignoring deeper questions. It's the position of an engineer rather than a fundamental research scientist.

> Relativity doesn't say that both an Earth-centric and solar-barycentric models are equally correct

I'm fairly sure it does. Of course, you'll get the same answer either way - the earth moves in an elliptical orbit around the sun and contributes a tiny amount of the total inertia of the system. But you can use either the sun or the earth as your frame of reference to calculate this.

It's explained quite well on wikipedia so I'll just quote that here:

> Albert Einstein and Leopold Infeld wrote in The Evolution of Physics (1938): "Can we formulate physical laws so that they are valid for all CS (=coordinate systems), not only those moving uniformly, but also those moving quite arbitrarily, relative to each other? If this can be done, our difficulties will be over. We shall then be able to apply the laws of nature to any CS. The struggle, so violent in the early days of science, between the views of Ptolemy and Copernicus would then be quite meaningless. Either CS could be used with equal justification. The two sentences, 'the sun is at rest and the Earth moves', or 'the sun moves and the Earth is at rest', would simply mean two different conventions concerning two different CS. Could we build a real relativistic physics valid in all CS; a physics in which there would be no place for absolute, but only for relative, motion? This is indeed possible!"[47]

> Despite giving more respectability to the geocentric view than Newtonian physics does,[48] relativity is not geocentric. Rather, relativity states that the Sun, the Earth, the Moon, Jupiter, or any other point for that matter could be chosen as a center of the Solar System with equal validity.

> Relativity agrees with Newtonian predictions that regardless of whether the Sun or the Earth are chosen arbitrarily as the center of the coordinate system describing the Solar System, the paths of the planets form (roughly) ellipses with respect to the Sun, not the Earth. With respect to the average reference frame of the fixed stars, the planets do indeed move around the Sun, which due to its much larger mass, moves far less than its own diameter and the gravity of which is dominant in determining the orbits of the planets (in other words, the center of mass of the Solar System is near the center of the Sun). The Earth and Moon are much closer to being a binary planet; the center of mass around which they both rotate is still inside the Earth, but is about 4,624 km (2,873 mi) or 72.6% of the Earth's radius away from the centre of the Earth (thus closer to the surface than the center).[citation needed]

> What the principle of relativity points out is that correct mathematical calculations can be made regardless of the reference frame chosen, and these will all agree with each other as to the predictions of actual motions of bodies with respect to each other. It is not necessary to choose the object in the Solar System with the largest gravitational field as the center of the coordinate system in order to predict the motions of planetary bodies, though doing so may make calculations easier to perform or interpret. A geocentric coordinate system can be more convenient when dealing only with bodies mostly influenced by the gravity of the Earth (such as artificial satellites and the Moon), or when calculating what the sky will look like when viewed from Earth (as opposed to an imaginary observer looking down on the entire Solar System, where a different coordinate system might be more convenient

https://en.m.wikipedia.org/wiki/Geocentric_model#relativity

See in particular this sentence:

> It is not necessary to choose the object in the Solar System with the largest gravitational field as the center of the coordinate system in order to predict the motions of planetary bodies, though doing so may make calculations easier to perform or interpret.

That's exactly the point I made above.

> Of course, you'll get the same answer either way - the earth moves in an elliptical orbit around the sun and contributes a tiny amount of the total inertia of the system.

That was my point. Saying "the earth moves in an elliptical orbit around the sun" is not compatible with what you wrote previously, "both of these are equally right," when one of the statements in question is that the Sun and planets move in orbits around the Earth.

This part of the Wikipedia quote underscores this:

The quote you provided describes the same distinction I was making: there is a predictive equivalence between a geocentric and heliocentric model, i.e. either coordinate system can give the correct results; but, the two models do not provide equivalent explanatory power.

For example, in the geocentric model, you have to explain why planets undergo both prograde and retrograde motion. If you're trying to go beyond simple prediction to understand what's happening, you need an interpretation of the model, beyond just treating it as a black box that spits out predictions.

The only correct interpretation of the model is the one in the two quotes above.

To bring this back to the original discussion, it seems extremely likely that e.g. the Copenhagen interpretation is much like the geocentric one - its notion of "collapse" is almost certainly something due to our perspective as macroscopic quantum objects interacting with microscopic quantum objects, much as prograde and retrograde motion are a result of our geocentric perspective. Even though one can make correct predictions under Copenhagen, it may be a red herring from an explanatory perspective.

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