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I know that Eliezer Yudkowsky is very controversial and some of his statements cannot be taken seriously, but I really liked his sequence of articles on QM. It

by runn1ng 10y ago

I know that Eliezer Yudkowsky is very controversial and some of his statements cannot be taken seriously, but I really liked his sequence of articles on QM. It made it a little bit more accessible to me, who knows very little about it. I cannot judge how accurate it is; but from googling around, it doesn't seem he does any strong errors. Also he makes some very strong statements in the end which I found preposterous (mainly, that Bayes reasoning is better than scientific reasoning, and that Bayes reasoning must lead to Many Worlds theory). The sequence is here http://lesswrong.com/lw/r5/the_quantum_physics_sequence/ http://lesswrong.com/lw/r5/the_quantum_physics_sequence/

danharaj 10y ago
One of the issues with engaging with Yudkowsky's posts is how verbose his arguments are. Fortunately, for something as well formalized as quantum mechanics, there's a succinct counter-example: A formalism of quantum mechanics that makes perfect sense with neither the idea of wavefunction collapse nor some abundance of ontologically dubious and extravagant entities (alternate universes you can never observe). That formalism is relational quantum mechanics. Accessible overview: https://plato.stanford.edu/entries/qm-relational/ https://plato.stanford.edu/entries/qm-relational/ In particular, this overview addresses the fundamental difference between Everett's theory and Rovelli's theory. Original paper: https://arxiv.org/abs/quant-ph/9609002 https://arxiv.org/abs/quant-ph/9609002 A fluffy paper by the same author about QFT and its relational nature: https://arxiv.org/abs/hep-th/9910131 https://arxiv.org/abs/hep-th/9910131 In short: The way you can evade the difficulties MWI addresses completely by changing one premise of the problem: that physical systems have states independent of their observers. In relational quantum mechanics, there is no universal wavefunction because there is no external observer of the universe. Call it the zero worlds interpretation. How parsimonious! There is an element of Yudkowsky's sequence that deals with relative configuration spaces, but this is a subtly different concept and is really just a discussion from a clever guy unequipped with the right concepts about the difference between, say, affine spaces and vector spaces or torsors and groups. The idea that there is a configuration space independent of the observer is the assumption he misses. In general I find Yudkowsky's extreme certainty in his own arguments to range from amusing to obnoxious. It's not hard to find places where uncertainty creeps in. It doesn't come from mistakes in his reasoning because what he considers he is usually meticulous about considering, but from what he doesn't consider.

by runn1ng 10y ago

danharaj 10y ago

One of the issues with engaging with Yudkowsky's posts is how verbose his arguments are. Fortunately, for something as well formalized as quantum mechanics, there's a succinct counter-example: A formalism of quantum mechanics that makes perfect sense with neither the idea of wavefunction collapse nor some abundance of ontologically dubious and extravagant entities (alternate universes you can never observe). That formalism is relational quantum mechanics. Accessible overview: https://plato.stanford.edu/entries/qm-relational/ https://plato.stanford.edu/entries/qm-relational/ In particular, this overview addresses the fundamental difference between Everett's theory and Rovelli's theory. Original paper: https://arxiv.org/abs/quant-ph/9609002 https://arxiv.org/abs/quant-ph/9609002 A fluffy paper by the same author about QFT and its relational nature: https://arxiv.org/abs/hep-th/9910131 https://arxiv.org/abs/hep-th/9910131 In short: The way you can evade the difficulties MWI addresses completely by changing one premise of the problem: that physical systems have states independent of their observers. In relational quantum mechanics, there is no universal wavefunction because there is no external observer of the universe. Call it the zero worlds interpretation. How parsimonious! There is an element of Yudkowsky's sequence that deals with relative configuration spaces, but this is a subtly different concept and is really just a discussion from a clever guy unequipped with the right concepts about the difference between, say, affine spaces and vector spaces or torsors and groups. The idea that there is a configuration space independent of the observer is the assumption he misses. In general I find Yudkowsky's extreme certainty in his own arguments to range from amusing to obnoxious. It's not hard to find places where uncertainty creeps in. It doesn't come from mistakes in his reasoning because what he considers he is usually meticulous about considering, but from what he doesn't consider.