10 ms·

The Zen Anti-Interpretation of Quantum Mechanics

93 points by nabla9 6y ago

im3w1l 6y ago
As I've pilosophized about many-worlds there is one thing I've recently come to believe is that there is a slight issue with his answer 7: We as people don't exist in a single world. Rather we have a certain non-zero "width" if you will in "probability-space". This would mean that "the fire" is already a little bit distributed based on what we can observe. This follows from heisenberg uncertainty. If a world is an assignment of a position to every particle, it cannot also assign them momentum: If you see position as fundamental then momentum is a phenomenon that exists "between-worlds" rather than inside them. And conversely if you see momentum as fundamental than position exists "between-worlds". When such fundemental things cannot exist in a single world, than I doubt that we can either.
- Ericson2314 6y ago
  Our uncertainty about the world can follow classically just fine.
- BalinKing 6y ago
  What if neither position nor momentum are fundamental, though (which, as I understand it, is the “default” for the math behind QM)? According to my understanding of the uncertainty principle, neither of them have values until their values are collapsed (whether it be through many worlds, pilot wave theory, or what have you).
adamnemecek 6y ago
All these explanations throw a bunch of things at you but don’t give you some succinct idea what it’s actually about I think that qm summarized in one sentence is the no-cloning theorem https://en.wikipedia.org/wiki/No-cloning_theorem https://en.wikipedia.org/wiki/No-cloning_theorem The connections to linear logic are very interesting. One can make the connection form qm to constructive math.
- 6gvONxR4sf7o 6y ago
  > All these explanations throw a bunch of things at you but don’t give you some succinct idea what it’s actually about After that sentence I was really expecting your Wikipedia link to point here: https://en.wikipedia.org/wiki/Koan https://en.wikipedia.org/wiki/Koan
- Strilanc 6y ago
  > I think that qm summarized in one sentence is the no-cloning theorem The no-cloning theorem isn't unique to quantum mechanics. As with many quantum paradoxes, you can translate it into an equivalent statistical paradox. The classical version of the no-cloning theorem is the statement that there's no operation that transforms one sample from a Bernoulli distribution with unknown parameter p into two independent samples from that distribution. Since there's classical no-cloning, it's a very bad idea to define quantum mechanics as that-thing-with-a-no-cloning-theorem. That definition isn't able to distinguish quantum mechanics from statistics.
the__alchemist 6y ago
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.
- Kranar 6y ago
  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.
  - the__alchemist 6y ago
    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!
- mef51 6y ago
  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.
bitdizzy 6y ago
The weirdness of quantum mechanics with respect to bases is very counterintuitive but makes perfect sense internal to the logic of the quantum world. It is a sort of relativity where there can be incompatible viewpoints. Namely, a hermitian operator is some view of the world, its eigenbasis tells you what you can see from that viewpoint. Two hermitian operators can be incompatible in that they can't be simultaneously diagnolized. Entanglement is another weirdness that makes perfect sense internally. The tensor product of projective hilbert spaces is not the same as the cartesian product. The segre embedding captures this. Theres more to the geometry of quantum phenomena than naively expected. The outcome of measurements collapsing to the eigenbasis of a hermitian operator has a beautiful an elegant geometric interpretation. It makes perfect sense really, just not classical sense. Decoherence explains why we see collapse to this set very well. What is utterly baffling and puzzling is that we only ever see one particular outcome. Decoherence cannot explain that and nothing in quantum mechanics explains that.
- cjfd 6y ago
  "What is utterly baffling and puzzling is that we only ever see one particular outcome." Actually, there is an answer to this. See e.g. https://arxiv.org/abs/quant-ph/0503009 https://arxiv.org/abs/quant-ph/0503009 tldr: if information is transferred from a microscopic quantum state to a macroscopic one, one always gets a collapse of the wave function.
  - prox 6y ago
    So it is a bit like a wave crashing at a beachhead?
    - ben_w 6y ago
      Any analogy we can build from everyday experience to try to explain quantum mechanics is as incorrect as any analogy a 17th century alchemist could use to explain a smartphone. The maths is what it is and does what it does, and if you play with things at that scale you can build a new intuition, but it just isn’t like the macroscopic world.
ukj 6y ago
Aaronson seems to be arriving at an understanding that is similar to what cross-compilers do in practice. By understanding other people’s interpretations you can translate between the “assembly languages” for their minds. You know what they will say, you know how they will react, you know what counter-arguments they will produce. You know how to paraphrase your words so they agree or disagree with you. You know how they think. He has predictive models for other minds. There is nothing to “understand” about QM at face value. Because “understanding” is always about prediction.
- drran 6y ago
  "Understanding" is always about reproduction. Reproduce quantum effects at human scale, so I will be able to watch them with my own eyes. IF I will be able to reproduce these effects in human scale experiments by myself AND derive my own formulas from these experiments, which will closely describe the results of quantum experiments, THEN we both will trust each other that we understand QM. Otherwise, it's a religion with rituals in math, not a science. 40+ years without much progress clearly demonstrates that.
  - ukj 6y ago
    I mean, sure. If you believe scale invariance holds.
    - drran 6y ago
      Scale effects are non-linear (sinusoidal, x^2, x^3, x^4). Some effects will not work at human scale, of course. IMHO, we can deal with them, or try to deal with them, at least, by adjusting of formulas. We can reproduce some 3D effects in 2D already, for better understanding of them, for example.
m_x 6y ago
Speaking of Zen and QM, I think a similar point of view is held by the french philosopher Michel Bitbol[0] in his introduction of QM to the Dalaï Lama : Quantum Theory, a theory with no view of the world ?[1]. Michel Bitbol is quite a thought provoking scholar (at least for me). Unfortunately there aren't many of his books translated in English. [0] http://michel.bitbol.pagesperso-orange.fr/ http://michel.bitbol.pagesperso-orange.fr/ [1] https://youtu.be/JzKKuPmk95g?t=2607 https://youtu.be/JzKKuPmk95g?t=2607
captainmuon 6y ago
Many thing in quantum mechanics point to an underlying reality. And I'm not talking about bohmian mechanics and hidden classical variables. I believe that is obviously wrong, since "location" and "momentum" are obviously emergent properties, as you can easily see when you play around with a wave packet and derive the uncertainty relation. There are so many equivalences between quantum theory and probability theory, beyond "QM is an extension of probability to complex numbers" and "square the amplitude to get the probability". For example, look at Feynman's path integral - where you sum up all possible ways to go from A to B, to get the transition amplitude. You can do a wick rotation (t -> it) and get a new expression related to a classical random walk. I hear you can even use a version of it in finance mathematics. Another example is superluminal signaling. It would seem like something superluminal is going on with entanglement. But nature conspires just so that we cannot use it for transmitting information. A beginner would try to explain it classically - imagine you have two boxes, and put a marble in one. Now find the marble in one box, and obviously it will not be in the second. But classical analogies cannot give the same statistics as QM. (Sorry, it's been a while, I have difficulties recalling the argument :-).) Anyway it seems like there must be an underlying reality that is "non-local" (in that it is not concerned with x, p, t, because these are emergent), and of which QM emerges as a statistical limit. There is an interesing idea from Gerard 't Hooft that this is a cellular automaton - the math seems to work out, but personally I feel that it should be a field theory (without any great justification as I'm just an armchair theorist).
- continuational 6y ago
  > imagine you have two boxes, and put a marble in one. Now find the marble in one box, and obviously it will not be in the second. But classical analogies cannot give the same statistics as QM. (Sorry, it's been a while, I have difficulties recalling the argument :-).) This nicely sums up every explanation on this topic I've ever encountered.
- typicalset 6y ago
  I'm not sure we have the same understanding of emergence, here (and I'm not going to insist on being precise). I would think being emergent has something to do with a structure being present in a system which is not a fundamental part of the description. Something like thought being emergent from connecting a group of neurons. Calling x, p, t, emergent, when they are co-ordinates in the conventional formulation of QM, is not this. I wouldn't call time emergent in the description of a simple harmonic oscillator, and I wouldn't call frequency emergent either. Could you elaborate on what you meant?
n4r9 6y ago
Imo the phrase "encodes everything there is to know about a physical system" already belies a certain amount of interpretation.
- happythomist 6y ago
  This is exactly right. So does "all our concepts are complicated grab bags of 'ontic' and 'epistemic'".
spark3k 6y ago
Is QM really trying very hard to tell us that spacetime is emergent? Space is emergent because: spooky action at a distance. Time is emergent because: delayed choice quantum eraser experiments.
- tim333 6y ago
  I've thought that before now, with respect to spooky action. There's an interesting seeming bit in the Feynman Lectures on Gravitation where he kind of demonstrates you can get Einstein type spacetime from the maths of a spin-2 particle though it's remained a bit beyond me to understand it. I even thought at one point I'd try to write a summary of his argument for Wikipedia but failed. It's not the most simple of things. The end bit I was thinking was "the fact is that a spin-two field has this geometrical interpretation; this is not something readily explainable--it is just marvelous." In section 8-4. But the math leading up to that is tricky.
  - captainmuon 6y ago
    As far as I understand it, you can decide which part of the dynamics you put into the spacetime, and which part into the fields. So a spin-2 field on a flat spacetime is equivalent to general relativity. (And you can't tell the difference because you can't detect individual gravitons, among other reasons.) A smiliar cool idea that I encountered in a string theory course, is when you have tachyons. They seem pretty bad because you can gain energy by creating more tachyons, and your spacetime would decay. But what it really means is that you have chosen a "wrong" spacetime, and you can transform the tachyons away by choosing a different background. (Handwaving here since I'm just an experimentalist ;-))
    - tim333 6y ago
      Thanks. I think handwavy is ok for this stuff as no one has really cracked the quantum gravity thing.
danielam 6y ago
In this vein and of possible interest: https://www.wolfson.cam.ac.uk/about/news/there-just-one-fundamental-thing-exists-jrf-proposes-new-ontology-quantum-mechanics https://www.wolfson.cam.ac.uk/about/news/there-just-one-fund... (Direct link to journal article can be found within.)
garyrob 6y ago
For the last 8 years I have been engaged in actual Zen practice, working on actual Zen koans with an actual Zen teacher in an actual Zen lineage that can be accurately traced back for a millennium or so. I will say that Aaronsen's "Zen Anti-Interpretation or quantum mechanics" has, as far as I can tell, an odd resonance with actual Zen. One of the koans I worked with recently: """ A monk once went to Högen of Seiryo before the midday meal to ask for instruction. Högen pointed to the bamboo blinds with his hand. At that moment, two monks who were there went over to the blinds and rolled them up in the same manner. Högen said, "One has gained, one has lost." """ A key aspect to the koan is that by "in the same manner" it is meant that there is actually no difference between them in any normal sense; Högen doesn't have access to some inner state of the monks that we don't have. But Högen was a great Zen master and knew what he was doing.
- abarker 6y ago
  Aaronson seems to be using the term Zen metaphorically, as a general path to some sort of "enlightenment" or "Zen state."
fineline 6y ago
I read this article more because I'm interested in Zen than QM. But it prompted a question for me. What (if any) is the relationship between QM (which I understand to manifest mainly at the level of particles and very small scales) and the science of complex non-linear dynamic systems (colloquially "chaos theory"). Both centre around the philosophical concept of unknowability, unpredictability, uncertainty. Both prompt questions around why the world is the way it is, rather than any of the other states it could have ended up in, which leads to wondering about whether alternate states could, or should, also exist. I personally find complexity more approachable, as it concerns phenomena that are at a more relatable scale - the weather, the economy, species evolution etc. Is there any intersection between QM and complex systems science in the conventional/institutional sense, e.g. in study or research? Or are they separate rabbit holes?
- beaconstudios 6y ago
  This is something I'm interested in as well (also being interested in Zen and systems theory). There's an interpretation of QM called hidden variables theory that essentially states that the probabilistic nature of quantum behaviour is due to QM being emergent behaviour from lower variables that we haven't discerned. It isn't in vogue, but it fits a systems perspective perfectly. Through this lens QM is a dynamical system, though perhaps not chaotic (I'm still not sure as to the boundary between dynamical and chaotic behaviour given both imply complex nonlinear causality). But then, a big issue with QM is that it's unintuitive, so that's probably confirmation bias on my part.
  - fineline 6y ago
    Thanks, I'll look into hidden variables.
perl4ever 6y ago
As someone who's mostly non-mathematical, every popularized or semi-popularized article about the subject of QM interpretations leaves me wondering why everyone is so steadfastly prejudiced against non-locality? It just doesn't seem that precious to me. It always seems like the odd one out.
- beaconstudios 6y ago
  because all our physics at the macro-scale have local causality. Also, this is just me but how does the speed of light constrain the speed of motion if quantum physics are non-local? There's no such thing as a speed limit if you can teleport information.
  - perl4ever 6y ago
    Well, people say you can't "teleport information". That so called quantum teleportation doesn't allow superluminal signaling. So that's just a fact about how the world works, I guess. What I'm saying is that people (who understand stuff I can't begin to comprehend) seem to dismiss out of hand an interpretation that includes nonlocality, but presumably it doesn't conflict with anything else that we actually observe whether you treat it one way or the other. It doesn't contradict all our physics with light speed limitations because it's defined consistently in the first place. I'm just taking this on faith, but it appears that there is no issue of reality being this or that, but more of an aesthetic problem where something implying faster than light action is just unpleasant because it seems like a universal principle isn't so universal. I want to read something popularized about what you get if you decide that an interpretation with nonlocality is just fine.
    - n4r9 6y ago
      As someone who is not steadfastly against non-locality: you have a sort of bizarre tension with special relativity, in which spacetime is explicitly locally causal. Tim Maudlin actually wrote an interesting and thorough book on this: https://www.google.com/url?q=https://www.amazon.co.uk/Quantum-Non-Locality-Relativity-Metaphysical-Intimations/dp/1444331272&sa=U&ved=2ahUKEwia8dzFy57vAhUnQUEAHbzYCDAQFjAHegQIAxAB&usg=AOvVaw34RtwBw6rhiTsIQTKJTU0Y https://www.google.com/url?q=https://www.amazon.co.uk/Quantu...

93 points by nabla9 6y ago

As I've pilosophized about many-worlds there is one thing I've recently come to believe is that there is a slight issue with his answer 7: We as people don't exist in a single world. Rather we have a certain non-zero "width" if you will in "probability-space". This would mean that "the fire" is already a little bit distributed based on what we can observe. This follows from heisenberg uncertainty. If a world is an assignment of a position to every particle, it cannot also assign them momentum: If you see position as fundamental then momentum is a phenomenon that exists "between-worlds" rather than inside them. And conversely if you see momentum as fundamental than position exists "between-worlds". When such fundemental things cannot exist in a single world, than I doubt that we can either.

Ericson2314 6y ago
Our uncertainty about the world can follow classically just fine.
BalinKing 6y ago
What if neither position nor momentum are fundamental, though (which, as I understand it, is the “default” for the math behind QM)? According to my understanding of the uncertainty principle, neither of them have values until their values are collapsed (whether it be through many worlds, pilot wave theory, or what have you).

adamnemecek 6y ago

All these explanations throw a bunch of things at you but don’t give you some succinct idea what it’s actually about I think that qm summarized in one sentence is the no-cloning theorem https://en.wikipedia.org/wiki/No-cloning_theorem https://en.wikipedia.org/wiki/No-cloning_theorem The connections to linear logic are very interesting. One can make the connection form qm to constructive math.

6gvONxR4sf7o 6y ago
> All these explanations throw a bunch of things at you but don’t give you some succinct idea what it’s actually about After that sentence I was really expecting your Wikipedia link to point here: https://en.wikipedia.org/wiki/Koan https://en.wikipedia.org/wiki/Koan
Strilanc 6y ago
> I think that qm summarized in one sentence is the no-cloning theorem The no-cloning theorem isn't unique to quantum mechanics. As with many quantum paradoxes, you can translate it into an equivalent statistical paradox. The classical version of the no-cloning theorem is the statement that there's no operation that transforms one sample from a Bernoulli distribution with unknown parameter p into two independent samples from that distribution. Since there's classical no-cloning, it's a very bad idea to define quantum mechanics as that-thing-with-a-no-cloning-theorem. That definition isn't able to distinguish quantum mechanics from statistics.

the__alchemist 6y ago

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.

Kranar 6y ago
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.
- the__alchemist 6y ago
  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!
mef51 6y ago
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.

bitdizzy 6y ago

The weirdness of quantum mechanics with respect to bases is very counterintuitive but makes perfect sense internal to the logic of the quantum world. It is a sort of relativity where there can be incompatible viewpoints. Namely, a hermitian operator is some view of the world, its eigenbasis tells you what you can see from that viewpoint. Two hermitian operators can be incompatible in that they can't be simultaneously diagnolized. Entanglement is another weirdness that makes perfect sense internally. The tensor product of projective hilbert spaces is not the same as the cartesian product. The segre embedding captures this. Theres more to the geometry of quantum phenomena than naively expected. The outcome of measurements collapsing to the eigenbasis of a hermitian operator has a beautiful an elegant geometric interpretation. It makes perfect sense really, just not classical sense. Decoherence explains why we see collapse to this set very well. What is utterly baffling and puzzling is that we only ever see one particular outcome. Decoherence cannot explain that and nothing in quantum mechanics explains that.

cjfd 6y ago
"What is utterly baffling and puzzling is that we only ever see one particular outcome." Actually, there is an answer to this. See e.g. https://arxiv.org/abs/quant-ph/0503009 https://arxiv.org/abs/quant-ph/0503009 tldr: if information is transferred from a microscopic quantum state to a macroscopic one, one always gets a collapse of the wave function.
- prox 6y ago
  So it is a bit like a wave crashing at a beachhead?
  - ben_w 6y ago
    Any analogy we can build from everyday experience to try to explain quantum mechanics is as incorrect as any analogy a 17th century alchemist could use to explain a smartphone. The maths is what it is and does what it does, and if you play with things at that scale you can build a new intuition, but it just isn’t like the macroscopic world.

ukj 6y ago

Aaronson seems to be arriving at an understanding that is similar to what cross-compilers do in practice. By understanding other people’s interpretations you can translate between the “assembly languages” for their minds. You know what they will say, you know how they will react, you know what counter-arguments they will produce. You know how to paraphrase your words so they agree or disagree with you. You know how they think. He has predictive models for other minds. There is nothing to “understand” about QM at face value. Because “understanding” is always about prediction.

drran 6y ago
"Understanding" is always about reproduction. Reproduce quantum effects at human scale, so I will be able to watch them with my own eyes. IF I will be able to reproduce these effects in human scale experiments by myself AND derive my own formulas from these experiments, which will closely describe the results of quantum experiments, THEN we both will trust each other that we understand QM. Otherwise, it's a religion with rituals in math, not a science. 40+ years without much progress clearly demonstrates that.
- ukj 6y ago
  I mean, sure. If you believe scale invariance holds.
  - drran 6y ago
    Scale effects are non-linear (sinusoidal, x^2, x^3, x^4). Some effects will not work at human scale, of course. IMHO, we can deal with them, or try to deal with them, at least, by adjusting of formulas. We can reproduce some 3D effects in 2D already, for better understanding of them, for example.

m_x 6y ago

Speaking of Zen and QM, I think a similar point of view is held by the french philosopher Michel Bitbol[0] in his introduction of QM to the Dalaï Lama : Quantum Theory, a theory with no view of the world ?[1]. Michel Bitbol is quite a thought provoking scholar (at least for me). Unfortunately there aren't many of his books translated in English. [0] http://michel.bitbol.pagesperso-orange.fr/ http://michel.bitbol.pagesperso-orange.fr/ [1] https://youtu.be/JzKKuPmk95g?t=2607 https://youtu.be/JzKKuPmk95g?t=2607

captainmuon 6y ago

Many thing in quantum mechanics point to an underlying reality. And I'm not talking about bohmian mechanics and hidden classical variables. I believe that is obviously wrong, since "location" and "momentum" are obviously emergent properties, as you can easily see when you play around with a wave packet and derive the uncertainty relation. There are so many equivalences between quantum theory and probability theory, beyond "QM is an extension of probability to complex numbers" and "square the amplitude to get the probability". For example, look at Feynman's path integral - where you sum up all possible ways to go from A to B, to get the transition amplitude. You can do a wick rotation (t -> it) and get a new expression related to a classical random walk. I hear you can even use a version of it in finance mathematics. Another example is superluminal signaling. It would seem like something superluminal is going on with entanglement. But nature conspires just so that we cannot use it for transmitting information. A beginner would try to explain it classically - imagine you have two boxes, and put a marble in one. Now find the marble in one box, and obviously it will not be in the second. But classical analogies cannot give the same statistics as QM. (Sorry, it's been a while, I have difficulties recalling the argument :-).) Anyway it seems like there must be an underlying reality that is "non-local" (in that it is not concerned with x, p, t, because these are emergent), and of which QM emerges as a statistical limit. There is an interesing idea from Gerard 't Hooft that this is a cellular automaton - the math seems to work out, but personally I feel that it should be a field theory (without any great justification as I'm just an armchair theorist).

continuational 6y ago
> imagine you have two boxes, and put a marble in one. Now find the marble in one box, and obviously it will not be in the second. But classical analogies cannot give the same statistics as QM. (Sorry, it's been a while, I have difficulties recalling the argument :-).) This nicely sums up every explanation on this topic I've ever encountered.
typicalset 6y ago
I'm not sure we have the same understanding of emergence, here (and I'm not going to insist on being precise). I would think being emergent has something to do with a structure being present in a system which is not a fundamental part of the description. Something like thought being emergent from connecting a group of neurons. Calling x, p, t, emergent, when they are co-ordinates in the conventional formulation of QM, is not this. I wouldn't call time emergent in the description of a simple harmonic oscillator, and I wouldn't call frequency emergent either. Could you elaborate on what you meant?

n4r9 6y ago

Imo the phrase "encodes everything there is to know about a physical system" already belies a certain amount of interpretation.

happythomist 6y ago
This is exactly right. So does "all our concepts are complicated grab bags of 'ontic' and 'epistemic'".

spark3k 6y ago

Is QM really trying very hard to tell us that spacetime is emergent? Space is emergent because: spooky action at a distance. Time is emergent because: delayed choice quantum eraser experiments.

tim333 6y ago
I've thought that before now, with respect to spooky action. There's an interesting seeming bit in the Feynman Lectures on Gravitation where he kind of demonstrates you can get Einstein type spacetime from the maths of a spin-2 particle though it's remained a bit beyond me to understand it. I even thought at one point I'd try to write a summary of his argument for Wikipedia but failed. It's not the most simple of things. The end bit I was thinking was "the fact is that a spin-two field has this geometrical interpretation; this is not something readily explainable--it is just marvelous." In section 8-4. But the math leading up to that is tricky.
- captainmuon 6y ago
  As far as I understand it, you can decide which part of the dynamics you put into the spacetime, and which part into the fields. So a spin-2 field on a flat spacetime is equivalent to general relativity. (And you can't tell the difference because you can't detect individual gravitons, among other reasons.) A smiliar cool idea that I encountered in a string theory course, is when you have tachyons. They seem pretty bad because you can gain energy by creating more tachyons, and your spacetime would decay. But what it really means is that you have chosen a "wrong" spacetime, and you can transform the tachyons away by choosing a different background. (Handwaving here since I'm just an experimentalist ;-))
  - tim333 6y ago
    Thanks. I think handwavy is ok for this stuff as no one has really cracked the quantum gravity thing.

danielam 6y ago

In this vein and of possible interest: https://www.wolfson.cam.ac.uk/about/news/there-just-one-fundamental-thing-exists-jrf-proposes-new-ontology-quantum-mechanics https://www.wolfson.cam.ac.uk/about/news/there-just-one-fund... (Direct link to journal article can be found within.)

garyrob 6y ago

For the last 8 years I have been engaged in actual Zen practice, working on actual Zen koans with an actual Zen teacher in an actual Zen lineage that can be accurately traced back for a millennium or so. I will say that Aaronsen's "Zen Anti-Interpretation or quantum mechanics" has, as far as I can tell, an odd resonance with actual Zen. One of the koans I worked with recently: """ A monk once went to Högen of Seiryo before the midday meal to ask for instruction. Högen pointed to the bamboo blinds with his hand. At that moment, two monks who were there went over to the blinds and rolled them up in the same manner. Högen said, "One has gained, one has lost." """ A key aspect to the koan is that by "in the same manner" it is meant that there is actually no difference between them in any normal sense; Högen doesn't have access to some inner state of the monks that we don't have. But Högen was a great Zen master and knew what he was doing.

abarker 6y ago
Aaronson seems to be using the term Zen metaphorically, as a general path to some sort of "enlightenment" or "Zen state."

fineline 6y ago

I read this article more because I'm interested in Zen than QM. But it prompted a question for me. What (if any) is the relationship between QM (which I understand to manifest mainly at the level of particles and very small scales) and the science of complex non-linear dynamic systems (colloquially "chaos theory"). Both centre around the philosophical concept of unknowability, unpredictability, uncertainty. Both prompt questions around why the world is the way it is, rather than any of the other states it could have ended up in, which leads to wondering about whether alternate states could, or should, also exist. I personally find complexity more approachable, as it concerns phenomena that are at a more relatable scale - the weather, the economy, species evolution etc. Is there any intersection between QM and complex systems science in the conventional/institutional sense, e.g. in study or research? Or are they separate rabbit holes?

beaconstudios 6y ago
This is something I'm interested in as well (also being interested in Zen and systems theory). There's an interpretation of QM called hidden variables theory that essentially states that the probabilistic nature of quantum behaviour is due to QM being emergent behaviour from lower variables that we haven't discerned. It isn't in vogue, but it fits a systems perspective perfectly. Through this lens QM is a dynamical system, though perhaps not chaotic (I'm still not sure as to the boundary between dynamical and chaotic behaviour given both imply complex nonlinear causality). But then, a big issue with QM is that it's unintuitive, so that's probably confirmation bias on my part.
- fineline 6y ago
  Thanks, I'll look into hidden variables.

perl4ever 6y ago

As someone who's mostly non-mathematical, every popularized or semi-popularized article about the subject of QM interpretations leaves me wondering why everyone is so steadfastly prejudiced against non-locality? It just doesn't seem that precious to me. It always seems like the odd one out.

beaconstudios 6y ago
because all our physics at the macro-scale have local causality. Also, this is just me but how does the speed of light constrain the speed of motion if quantum physics are non-local? There's no such thing as a speed limit if you can teleport information.
- perl4ever 6y ago
  Well, people say you can't "teleport information". That so called quantum teleportation doesn't allow superluminal signaling. So that's just a fact about how the world works, I guess. What I'm saying is that people (who understand stuff I can't begin to comprehend) seem to dismiss out of hand an interpretation that includes nonlocality, but presumably it doesn't conflict with anything else that we actually observe whether you treat it one way or the other. It doesn't contradict all our physics with light speed limitations because it's defined consistently in the first place. I'm just taking this on faith, but it appears that there is no issue of reality being this or that, but more of an aesthetic problem where something implying faster than light action is just unpleasant because it seems like a universal principle isn't so universal. I want to read something popularized about what you get if you decide that an interpretation with nonlocality is just fine.
  - n4r9 6y ago
    As someone who is not steadfastly against non-locality: you have a sort of bizarre tension with special relativity, in which spacetime is explicitly locally causal. Tim Maudlin actually wrote an interesting and thorough book on this: https://www.google.com/url?q=https://www.amazon.co.uk/Quantum-Non-Locality-Relativity-Metaphysical-Intimations/dp/1444331272&sa=U&ved=2ahUKEwia8dzFy57vAhUnQUEAHbzYCDAQFjAHegQIAxAB&usg=AOvVaw34RtwBw6rhiTsIQTKJTU0Y https://www.google.com/url?q=https://www.amazon.co.uk/Quantu...