gjm avers “Landsberg that has a section headed “Clash of cultures” but it could not by any reasonable stretch be called an essay. It’s only a few paragraphs long.”
LOL … gjm, you must really dislike Lincoln’s ultra-short Gettysburg Address!
More seriously, isn’t the key question whether Landsberg’s essay is correct to assert that “there are language and even philosophical barriers to be overcome”, in communicating modern geometric insights to STEM researchers trained in older mathematical techniques?
Most seriously of all, gjm, please let me express the hope that the various references that you have pursued have helped to awaken an appreciation of the severe and regrettable mathematical limitations that are inherent in the essays of Less Wrong’sQuantum Physics Sequence, including in particular Eliezer_Yudkowsky’s essay Quantum Physics Revealed As Non-Mysterious.
The burgeoning 21st century literature of geometric dynamics helps us to appreciate that the the 20th century mathematical toolkit of Less Wrong’s quantum essays perhaps will turn out to be not so much “less wrong” as “not even wrong,” in the sense that Less Wrong’s quantum essays are devoid of the geometric dynamical ideas that are flowering so vigorously in the contemporary STEM literature.
This is of course very good news for young researchers! :)
you must really dislike Lincoln’s ultra-short Gettysburg Address!
No, I think it’s excellent (though I prefer the PowerPoint version), but it isn’t an essay.
let me express the hope that the various references [...] have helped to awaken an appreciation of the [...] mathematical limitations that are inherent in [...] Less Wrong’s Quantum Physics Sequence
That sentence appears to me to embody some assumptions you’re not in a position to make reliably. Notably: That I think, or thought until John Sidles kindly enlightened me, that Eliezer’s QM essays are anything like a complete exposition of QM. As it happens, that wasn’t my opinion; for that matter I doubt it is or was even Eliezer’s.
In particular, when Eliezer says that QM is “non-mysterious” I don’t think he means that everything about it is understood, that there are no further scientific puzzles to solve. He certainly doesn’t mean it isn’t possible to pick a mathematical framework for talking about QM and then contemplate generalizations. He’s arguing against a particular sort of mysterianism one often hears in connection with QM—the sort that says, roughly, “QM is counterintuitive, which means no one really understands it or can be expected to understand it, so the right attitude towards QM is one of quasi-mystical awe”, which is the kind of thing that makes Chopraesque quantum woo get treated with less contempt than it deserves.
Even Newtonian mechanics is mysterious in the sense that there are unsolved problems associated with it. (For instance: What are all the periodic 3-body trajectories? What is the right way to think about the weird measure-zero situations—involving collisions of more than two particles—in which the usual rules of Newtonian dynamics constrain what happens next without, prima facie, fully determining it?) But no one talks about Newtonian mechanics in the silly way some people talk about quantum mechanics, and it’s that sort of quantum silliness Eliezer is (at least, as I understand it) arguing against.
I think at least one of us has a serious misunderstanding of what’s generally meant by the phrase “not even wrong”. To me, it means “sufficiently vague or confused that it doesn’t even yield the sort of testable predictions that would allow it to be refuted”, which doesn’t seem to me to be an accurate description of conventional 20th-century quantum mechanics. It might, indeed, turn out that conventional 20th-century QM is a severely incomplete description of reality, and that in some situations it gives badly wrong predictions, and that some such generalization as you favour will do better, much as relativity and QM improved on classical physics in ways that radically revised our picture of what the universe fundamentally is. But classical physics was not “not even wrong”. It was an excellent body of ideas. It explained a lot, and it enabled a lot of correct predictions and useful inventions. It was wrong but clear and useful. It was the exact opposite of “not even wrong”.
Finally and incidentally: What impression do you think your tone gives to your readers? What impression are you hoping for? I ask because I think the reality may not match your hopes.
gjm avers: ‘When Eliezer says that QM is “non-mysterious’ … He’s arguing against a particular sort of mysterianism”
That may or may not be the case, but there is zero doubt that this assertion provides rhetorical foundations for the essay And the Winner is… Many-Worlds!.
A valuable service of the mathematical literature relating to geometric mechanics is that it instills a prudent humility regarding assertions like “the Winner is… Many-Worlds!” A celebrated meditation of Alexander Grothendieck expresses this humility:
“A different image came to me a few weeks ago. The unknown thing to be known appeared to me as some stretch of earth or hard marl, resisting penetration … the sea advances insensibly in silence, nothing seems to happen, nothing moves, the water is so far off you hardly hear it … yet it finally surrounds the resistant substance.”
Surely in regard quantum mechanics, the water of our understanding is far from covering the rocks of our ignorance!
As for the tone of my posts, the intent is that people who enjoy references and quotations will take no offense, and people who do not enjoy them can simply pass by.
It seems perfectly possible to me—I make no claims about whether it’s actually true—that the following could all be the case. (1) Of the various physical theories in the possession of the human race that are definite enough to be assessed, one of the clear winners is the Standard Model. (2) Of the various ways to understand the quantum mechanics involved in the Standard Model, the clear winner is “many worlds”. (3) The known lacunae in our understanding of physics make it clear that further conceptual advances will be needed before we can claim to understand everything. (4) Those conceptual advances could take just about any form, and everything we currently think we know is potentially up for grabs. (5) “Many worlds” is not uniquely under threat from these future conceptual advances—everything is up for grabs—and the possibility of future conceptual revolutions doesn’t call for any more caution about “many worlds” than it does for caution about, say, the inseparability of space and time.
In other words: The fact that science is hard and not yet finished is indeed reason for epistemic humility—about everything; but pointing to some particular thing alleged to be a discovery of modern science and saying “no, wait, it could turn out to be wrong” is not justifiable by that fact alone, unless you are happy to do the same for all other alleged discoveries of modern science.
My guess is that you have some other reasons for being skeptical about the many-worlds interpretation, besides the very general fact that quantum mechanics might some day be the subject of a great scientific upheaval. But you haven’t said what they are.
My point about your tone is not concerned with the fact that you include references and quotations, and taking offence isn’t the failure mode you might need to worry about. The danger, rather, is that you come across as pushing, with an air of smug superiority, a non-standard view of the present state of science, and that this is liable to pattern-match in people’s brains to a host of outright cranks. If you prefer not to be dismissed as a crank, you might want to adjust your tone.
(If, on the other hand, you don’t care whether you are dismissed as a crank, then the question in some minds will be “Why should I take him seriously when he doesn’t seem to do so himself?”.)
gjm asserts “Of the various ways to understand the quantum mechanics involved in the Standard Model, the clear winner is “many worlds”
LOL … by that lenient standard, the first racehorse out of the gate, or the first sprinter out of the blocks, can reasonably be proclaimed “the clear winner” … before the race is even finished!
That’s a rational announcement only for very short races. Surely there is very little evidence that the course that finishes at comprehensive understanding of Nature’s dynamics … is a short course?
LOL … gjm, you must really dislike Lincoln’s ultra-short Gettysburg Address!
More seriously, isn’t the key question whether Landsberg’s essay is correct to assert that “there are language and even philosophical barriers to be overcome”, in communicating modern geometric insights to STEM researchers trained in older mathematical techniques?
Most seriously of all, gjm, please let me express the hope that the various references that you have pursued have helped to awaken an appreciation of the severe and regrettable mathematical limitations that are inherent in the essays of Less Wrong’s Quantum Physics Sequence, including in particular Eliezer_Yudkowsky’s essay Quantum Physics Revealed As Non-Mysterious.
The burgeoning 21st century literature of geometric dynamics helps us to appreciate that the the 20th century mathematical toolkit of Less Wrong’s quantum essays perhaps will turn out to be not so much “less wrong” as “not even wrong,” in the sense that Less Wrong’s quantum essays are devoid of the geometric dynamical ideas that are flowering so vigorously in the contemporary STEM literature.
This is of course very good news for young researchers! :)
No, I think it’s excellent (though I prefer the PowerPoint version), but it isn’t an essay.
That sentence appears to me to embody some assumptions you’re not in a position to make reliably. Notably: That I think, or thought until John Sidles kindly enlightened me, that Eliezer’s QM essays are anything like a complete exposition of QM. As it happens, that wasn’t my opinion; for that matter I doubt it is or was even Eliezer’s.
In particular, when Eliezer says that QM is “non-mysterious” I don’t think he means that everything about it is understood, that there are no further scientific puzzles to solve. He certainly doesn’t mean it isn’t possible to pick a mathematical framework for talking about QM and then contemplate generalizations. He’s arguing against a particular sort of mysterianism one often hears in connection with QM—the sort that says, roughly, “QM is counterintuitive, which means no one really understands it or can be expected to understand it, so the right attitude towards QM is one of quasi-mystical awe”, which is the kind of thing that makes Chopraesque quantum woo get treated with less contempt than it deserves.
Even Newtonian mechanics is mysterious in the sense that there are unsolved problems associated with it. (For instance: What are all the periodic 3-body trajectories? What is the right way to think about the weird measure-zero situations—involving collisions of more than two particles—in which the usual rules of Newtonian dynamics constrain what happens next without, prima facie, fully determining it?) But no one talks about Newtonian mechanics in the silly way some people talk about quantum mechanics, and it’s that sort of quantum silliness Eliezer is (at least, as I understand it) arguing against.
I think at least one of us has a serious misunderstanding of what’s generally meant by the phrase “not even wrong”. To me, it means “sufficiently vague or confused that it doesn’t even yield the sort of testable predictions that would allow it to be refuted”, which doesn’t seem to me to be an accurate description of conventional 20th-century quantum mechanics. It might, indeed, turn out that conventional 20th-century QM is a severely incomplete description of reality, and that in some situations it gives badly wrong predictions, and that some such generalization as you favour will do better, much as relativity and QM improved on classical physics in ways that radically revised our picture of what the universe fundamentally is. But classical physics was not “not even wrong”. It was an excellent body of ideas. It explained a lot, and it enabled a lot of correct predictions and useful inventions. It was wrong but clear and useful. It was the exact opposite of “not even wrong”.
Finally and incidentally: What impression do you think your tone gives to your readers? What impression are you hoping for? I ask because I think the reality may not match your hopes.
That may or may not be the case, but there is zero doubt that this assertion provides rhetorical foundations for the essay And the Winner is… Many-Worlds!.
A valuable service of the mathematical literature relating to geometric mechanics is that it instills a prudent humility regarding assertions like “the Winner is… Many-Worlds!” A celebrated meditation of Alexander Grothendieck expresses this humility:
Surely in regard quantum mechanics, the water of our understanding is far from covering the rocks of our ignorance!
As for the tone of my posts, the intent is that people who enjoy references and quotations will take no offense, and people who do not enjoy them can simply pass by.
It seems perfectly possible to me—I make no claims about whether it’s actually true—that the following could all be the case. (1) Of the various physical theories in the possession of the human race that are definite enough to be assessed, one of the clear winners is the Standard Model. (2) Of the various ways to understand the quantum mechanics involved in the Standard Model, the clear winner is “many worlds”. (3) The known lacunae in our understanding of physics make it clear that further conceptual advances will be needed before we can claim to understand everything. (4) Those conceptual advances could take just about any form, and everything we currently think we know is potentially up for grabs. (5) “Many worlds” is not uniquely under threat from these future conceptual advances—everything is up for grabs—and the possibility of future conceptual revolutions doesn’t call for any more caution about “many worlds” than it does for caution about, say, the inseparability of space and time.
In other words: The fact that science is hard and not yet finished is indeed reason for epistemic humility—about everything; but pointing to some particular thing alleged to be a discovery of modern science and saying “no, wait, it could turn out to be wrong” is not justifiable by that fact alone, unless you are happy to do the same for all other alleged discoveries of modern science.
My guess is that you have some other reasons for being skeptical about the many-worlds interpretation, besides the very general fact that quantum mechanics might some day be the subject of a great scientific upheaval. But you haven’t said what they are.
My point about your tone is not concerned with the fact that you include references and quotations, and taking offence isn’t the failure mode you might need to worry about. The danger, rather, is that you come across as pushing, with an air of smug superiority, a non-standard view of the present state of science, and that this is liable to pattern-match in people’s brains to a host of outright cranks. If you prefer not to be dismissed as a crank, you might want to adjust your tone.
(If, on the other hand, you don’t care whether you are dismissed as a crank, then the question in some minds will be “Why should I take him seriously when he doesn’t seem to do so himself?”.)
LOL … by that lenient standard, the first racehorse out of the gate, or the first sprinter out of the blocks, can reasonably be proclaimed “the clear winner” … before the race is even finished!
That’s a rational announcement only for very short races. Surely there is very little evidence that the course that finishes at comprehensive understanding of Nature’s dynamics … is a short course?
As for my own opinions in regard to quantum dynamical systems, they are more along the lines of here are some questions that are mathematically well-posed and are interesting to engineers and scientists alike … and definitely not along the lines of “here are the answers to those questions”!
Actually I clearly and explicitly went out of my way to say I wasn’t asserting that.
Bored of being laughed at out loud now. (Twice in one short thread is enough.) Bye.
Goodbye, gjm. The impetus that your posts provided to post thought-provoking mathematical links will be missed. :)