10 ms·

Do electrons think? (1949)

71 points by benryon 8y ago

crazygringo 8y ago
Note that, contrary to popular understanding, it isn't even established that quantum mechanics is indeterminate or not subject to strict cause-and-effect. It's indeterminate according to the mainstream Copenhagen interpretation, but de Broglie–Bohm theory [1] ("pilot wave theory") is an interpretation that is entirely deterministic, and its assumptions result in exactly the same final equations as the Copenhagen one. But every particle always has a definite position+momentum and there's no notion of wave collapse or philosophical trickiness of what constitutes an "observer". For more on the historical reasons why Copenhagen became mainstream and de Broglie-Bohm didn't, see [2]. [1] https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory [2] http://qr.ae/TUNXvC http://qr.ae/TUNXvC
- Osmium 8y ago
  Discussion here [0], also recommend this lecture[1]. I'm personally not a fan, but I like that people talk about it :) Dogma isn't good for anyone! [0] https://news.ycombinator.com/item?id=13198025 https://news.ycombinator.com/item?id=13198025 [1] http://www.tcm.phy.cam.ac.uk/~mdt26/PWT/lectures/bohm7.pdf http://www.tcm.phy.cam.ac.uk/~mdt26/PWT/lectures/bohm7.pdf
- deleted 8y ago
  [deleted]
- jmcmichael 8y ago
  In this instance, the popular understanding corresponds to the latest research better than realist theories like pilot-wave theory. Proponents of realist interpretations of QM have relied for decades on identifying possible classical channels of relativistic communication, or theorizing the existence of hidden variables. The double slit experiment has been used in various forms to, over time, eliminate these channels. I'm not a physicist, but the language that they are using quite a few papers leads me to believe that these channels have been closed, and the realists are out of remaining options for maintaining realism. For instance: An experimental test of non-local realism, 2007 https://arxiv.org/abs/0704.2529 https://arxiv.org/abs/0704.2529 Wherein the authors show, using previously untested correlations between two entangled photons, that maintaining realist interpretations of quantum mechanics (such as pilot-wave theory) as a fundamental concept require the introduction of locality-defying 'action at a distance' actions. Quantum erasure with causally disconnected choice, 2012 https://arxiv.org/abs/1206.6578 https://arxiv.org/abs/1206.6578 Wherein the authors, using an interferometric quantum eraser experiment, eliminate past and future communication channels by enforcing Einstein locality via a mechanism that I don't understand yet. They conclude that, "No naive realistic picture is compatible with our results because whether a quantum could be seen as showing particle- or wave-like behavior would depend on a causally disconnected choice. It is therefore suggestive to abandon such pictures altogether." Experimental non-classicality of an indivisible quantum system, 2011 https://arxiv.org/abs/1106.4481 https://arxiv.org/abs/1106.4481 I understand even less of this one, looks like it has to do with performing the kinds of simultaneous measurements of various properties that one would expect to be able to, if realist interpretations were true. They conclude, "Not only is a single qutrit the simplest system in which such a contradiction is possible, but, even more importantly, the contradiction cannot result from entanglement, because such a system is indivisible, and it does not even allow the concept of entanglement between subsystems." UPDATE: Experimental loophole-free violation of a Bell inequality using entangled electron spins separated by 1.3 km 2015 https://arxiv.org/abs/1508.05949v1 https://arxiv.org/abs/1508.05949v1 "For more than 80 years, the counterintuitive predictions of quantum theory have stimulated debate about the nature of reality. ... In the past decades, numerous ingenious Bell inequality tests have been reported. However, because of experimental limitations, all experiments to date required additional assumptions to obtain a contradiction with local realism, resulting in loopholes. Here we report on a Bell experiment that is free of any such additional assumption and thus directly tests the principles underlying Bell's inequality. ... This result rules out large classes of local realist theories, and paves the way for implementing device-independent quantum-secure communication and randomness certification." I'm not aware of any significant challenges to these studies.
  - deleted 8y ago
    [deleted]
  - thraway180306 8y ago
    It would help if these weren't all from the same single source: Zeilinger's Vienna group and friends. On the other hand formalism works seamlessly mathematically, which cannot be said of standard quantum mechanics. Even this year's Fields medalist Figalli has a paper on how good things are in Bohmian land.
    - jmcmichael 8y ago
      Fine, here's another from Ronald Hensen at Delft: Experimental loophole-free violation of a Bell inequality using entangled electron spins separated by 1.3 km 2015 https://arxiv.org/abs/1508.05949v1 https://arxiv.org/abs/1508.05949v1 "...This result rules out large classes of local realist theories, and paves the way for implementing device-independent quantum-secure communication and randomness certification. "
      - akvadrako 8y ago
        This isn't relevant because Bohm's theory isn't local. There are much stronger results like PBR ruling out a large class of non-local realist theories, but that also doesn't include pilot wave theory. No known experiment can rule it out because it's predictions equal those of Copenhagen.
      - thraway180306 8y ago
        This is something different. Zeilinger paints himself disproving realism alone and has a well known philosophical stance/bias here. Local realism testing here however is about being both local and realist, and pilot waves aren't local to begin with.
        jmcmichael 8y ago
        Yeah, that makes sense. Do you have an example of Zeilinger's writing where he discusses his philosophical stance? Is a philosophical stance something you believe that a physicist shouldn't have?
- lmm 8y ago
  It's just many-worlds style wave-function realism with some extra epicycles on top. Treating the wavefunction as physically real is perfectly reasonable. Treating the wavefunction as physically real and then assuming there are also pseudoclassical particles on top adds nothing except appealing to the confused - "oh no, the particles aren't in a superposition, the particles are just ordinary classical particles... all of whose properties are determined by the pilot wave... which is in a superposition. Totally different."
  - thraway180306 8y ago
    Not true, a lot of mathematical problems behave better (but other semiclassical approaches also exist). As for the epicycles comparison, it's actually apt. They could have given complex plane and Fourier analysis for free if they had a chance (not to mention Copernicus actually used more of them than Ptolemy)(which incidentally is also the case with Many-World-necessiated landscapes and parameter spaces - just as much additional layer but with additional problems that are, in contrast, untractable by current math).
    - deleted 8y ago
      [deleted]
  - westoncb 8y ago
    > Treating the wavefunction as physically real is perfectly reasonable. What's your justification for that? I remember Arthur Eddington pointing out that it could be interpreted as modeling our limited knowledge of a quantum system just as well as its 'physical reality'. But there's obviously justification for the first one, while the second one appears to be a large unjustified leap.
    - lmm 8y ago
      > What's your justification for that? Occam's razor. The wavefunction is the simplest construct that explains our experimental results (it appears in every interpretation to some degree or another, certainly in pilot wave theory where it is the pilot wave), so it's simplest to assume it just is what's really happening. > I remember Arthur Eddington pointing out that it could be interpreted as modeling our limited knowledge of a quantum system just as well as its 'physical reality'. Hidden variable approaches are incompatible with our experimental results unless you introduce some seriously undesirable properties (e.g. nonlocality). I didn't say that wavefunction realism is the only reasonable approach, just that it's a reasonable approach. Pilot wave theory isn't - it introduces an extra layer of complexity justified by nothing more than human intuition (not even innate intuition, but the experience of classical mechanics).
- tpfour 8y ago
  I think you are abusing language here, probably not intentionally, and it distracts from the actual issue. You seem to understand the difference but for those who don't, here's a crucial distinction that's often overlooked by laypeople: The Schrödinger (Dirac) equation itself is deterministic. Given a wavefunction at time t=t0, you can calculate its evolution to time t=t1. What is indeterminate is the observation of the observable. The distribution of observations is entirely determined. Only the result of a single observation is indeterminate: in the limit of infinite measurements, you would get the probability distribution back which itself is determinate. The various "interpretations" concern themselves with what happens at the time of measurement. For example, the Copenhagen interpretation says that the wavefunction, which was evolving deterministically, mutates into a new wavefunction which itself evolves deterministically. This act of going from one to the other is considered indeterminate and is given the name of "collapse". However the dynamics of each wavefunction is entirely determinate.
- tbabb 8y ago
  De Broglie-Bohm is probably not the correct theory, since (if I am not mistaken) it's not reconcilable with relativity, and has a host of other problems which led its original proponents to abandon it. Copenhagen is also probably not correct, though it is still frustratingly mainstream. Copenhagen has the well known problem of lacking a physical definition of "observer", but it also has conflicts with delayed choice quantum eraser experiments (which suggest that the wavefunction never collapses), and contradictions that arise when you try to locate the proposed wave collapse in spacetime. The Everett many-worlds interpretation is gaining favor, and has none of the problems of the other two pictures. In the Everett view, scientists and experiments and instruments and universes are ensembles of particles like any other, and enter superpositions upon interacting with other systems in superposition. In a sense, every possible outcome of a quantum measurement actually happens in due proportion to the probabilities described by quantum mechanics, but upon becoming entangled with the experiment result, the different outcomes can no longer influence or measure each other. It is the most ontologically minimal theory, since it proposes no other events or laws beyond the already-known laws of quantum mechanics.
  - effie 8y ago
    In the Everettian interpretation, experiments do not have results (!) and it is not clear what probability even means, much less how the Born rule and observed statistics arise. That's because it is not a theory about our world, but about an imagined world where the only things existing is the psi function. > every possible outcome of a quantum measurement actually happens in due proportion to the probabilities described by quantum mechanics This cannot work, because those probabilities are defined by a basis in Hilbert space and that basis is defined by details of the experiment, which does not actually happen in the Everettian view.
    - tbabb 8y ago
      I am not sure what you mean by "experiments do not have results." A measurement in Everett is the environment becoming entangled with the measured system, and a "result" is a particular basis of the combined wavefunction.
- tntn 8y ago
  I'm a big fan of epistemological interpretations of QM. Everything becomes far less mysterious when it is a theory of knowledge, IMO. Wavefunction collapse? No wonder it collapsed: it represents your knowledge and you just observed the system.
  - retsibsi 8y ago
    That (to my complete layman's eye) seems reasonable, but is it really much more than shuffling labels around? It seems the 'deeper' mystery remains: what is going on at the fundamental level of reality? (Or, in other words, why do our observations have these properties?) Whether or not that question is answerable -- or even meaningful -- I think we'll always be driven to ask it.
- kjeetgill 8y ago
  I'm not super knowledgeable but I love this series, Looking Glass Universe, on the subject [0,1]. Specifically, she goes into some common but wrong beliefs about Bohemian Mechanics including that there is NO quantum weirdness. There is - it's called contextually. I don't know more than that. [0]: https://www.youtube.com/watch?v=r0plv_nIzsQ&t=2s https://www.youtube.com/watch?v=r0plv_nIzsQ&t=2s [1]: https://www.youtube.com/watch?v=Qz4CHI_W-TA https://www.youtube.com/watch?v=Qz4CHI_W-TA
MichaelAO 8y ago
Interesting interview with Basil Hiley (collaborator with David Bohm) on this topic: https://www.youtube.com/watch?v=wayQn0uVIvE https://www.youtube.com/watch?v=wayQn0uVIvE
macmac 8y ago
No.
- amelius 8y ago
  From the article: > To think that such a particle can think is so absurd, that I might give the answer “No” and have my talk over. However, (...)
- Koshkin 8y ago
  Well, for most definitions of 'think,' sure. But they can get excited - at least for some definitions of excitement.
panic 8y ago
I wonder what Schrödinger would have thought of the Free Will Theorem: https://arxiv.org/pdf/quant-ph/0604079.pdf https://arxiv.org/pdf/quant-ph/0604079.pdf
- effie 8y ago
  I think he would not like it. The theorem is underwhelming and uses misleading attention-seeking terminology. A more appropriate way to state it is, I think, this: if experiment settings violate determinism, its results have to violate determinism as well. To the author's credit, they say as much in the introduction themselves - "I saw you put the fish in".
Koshkin 8y ago
[Meta] A light, hard to read shade of gray. (Never understood why would anyone want to do that to the reader.)
- stephengillie 8y ago
  HN uses the same poor text contrast to highlight unpopular opinions.
edem 8y ago
From what I understand "seeing" is an active proccess, since it needs light. If we want to observe small things we need more precise light, which means more energy. The problem is not that small particles are somehow become aware when we observe, but the observation itself adds energy to the system, thus alters it. Is this correct?
- stephengillie 8y ago
  "Observing" means entangling with photons which have previously been entangled with the observed object. Thus, viewing an object means changing its state in such a way that you're temporarily also part of its state, forming an entropy gradient to gain energy/information from it.
  - IAmGraydon 8y ago
    That is completely incorrect.
mentos 8y ago
If electrons are the lowest level of granularity when it comes to determining state in computers then maybe it is the same in the mind? I imagine a computer made of silicon with the trillions of grooves that the mind has in biological form would find itself to have a conscious just the same. Remove the silicon from the computer or biomass from the brain leaving just electrons behind and you would have a network I would argue gives rise to the seat of consciousness.
beautifulfreak 8y ago
I wonder if anyone here would be so kind as to explain Schrodinger's argument. I'm not grasping it. Is he making a fundamental point about the degrees of freedom an electron can have, delimiting ideas about how a brain can process thought with the help of self-willed electrons? Or is it confined to whether an electron itself can have thought. What point is he making in the debate about whether humans are automata? I'll read it again, but it's subtle and I might not understand quantum mechanics sufficiently to understand it.
- Tomminn 8y ago
  He's saying that just because the movements of particles are not predictable doesn't mean you all of a sudden get to claim "free will"-- the ability to somehow impose an arbitrary desire in the chain of causality between your sense experiences and your actions. In order for you to have "free will" in this classical sense, you'd have to control the "slit" the electrons "swerve" through. But you don't. They just act randomly. They're not the things that impose your will. Your will is still an illusion.

71 points by benryon 8y ago

Note that, contrary to popular understanding, it isn't even established that quantum mechanics is indeterminate or not subject to strict cause-and-effect. It's indeterminate according to the mainstream Copenhagen interpretation, but de Broglie–Bohm theory [1] ("pilot wave theory") is an interpretation that is entirely deterministic, and its assumptions result in exactly the same final equations as the Copenhagen one. But every particle always has a definite position+momentum and there's no notion of wave collapse or philosophical trickiness of what constitutes an "observer". For more on the historical reasons why Copenhagen became mainstream and de Broglie-Bohm didn't, see [2]. [1] https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory https://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory [2] http://qr.ae/TUNXvC http://qr.ae/TUNXvC

Osmium 8y ago
Discussion here [0], also recommend this lecture[1]. I'm personally not a fan, but I like that people talk about it :) Dogma isn't good for anyone! [0] https://news.ycombinator.com/item?id=13198025 https://news.ycombinator.com/item?id=13198025 [1] http://www.tcm.phy.cam.ac.uk/~mdt26/PWT/lectures/bohm7.pdf http://www.tcm.phy.cam.ac.uk/~mdt26/PWT/lectures/bohm7.pdf
deleted 8y ago
[deleted]
jmcmichael 8y ago
In this instance, the popular understanding corresponds to the latest research better than realist theories like pilot-wave theory. Proponents of realist interpretations of QM have relied for decades on identifying possible classical channels of relativistic communication, or theorizing the existence of hidden variables. The double slit experiment has been used in various forms to, over time, eliminate these channels. I'm not a physicist, but the language that they are using quite a few papers leads me to believe that these channels have been closed, and the realists are out of remaining options for maintaining realism. For instance: An experimental test of non-local realism, 2007 https://arxiv.org/abs/0704.2529 https://arxiv.org/abs/0704.2529 Wherein the authors show, using previously untested correlations between two entangled photons, that maintaining realist interpretations of quantum mechanics (such as pilot-wave theory) as a fundamental concept require the introduction of locality-defying 'action at a distance' actions. Quantum erasure with causally disconnected choice, 2012 https://arxiv.org/abs/1206.6578 https://arxiv.org/abs/1206.6578 Wherein the authors, using an interferometric quantum eraser experiment, eliminate past and future communication channels by enforcing Einstein locality via a mechanism that I don't understand yet. They conclude that, "No naive realistic picture is compatible with our results because whether a quantum could be seen as showing particle- or wave-like behavior would depend on a causally disconnected choice. It is therefore suggestive to abandon such pictures altogether." Experimental non-classicality of an indivisible quantum system, 2011 https://arxiv.org/abs/1106.4481 https://arxiv.org/abs/1106.4481 I understand even less of this one, looks like it has to do with performing the kinds of simultaneous measurements of various properties that one would expect to be able to, if realist interpretations were true. They conclude, "Not only is a single qutrit the simplest system in which such a contradiction is possible, but, even more importantly, the contradiction cannot result from entanglement, because such a system is indivisible, and it does not even allow the concept of entanglement between subsystems." UPDATE: Experimental loophole-free violation of a Bell inequality using entangled electron spins separated by 1.3 km 2015 https://arxiv.org/abs/1508.05949v1 https://arxiv.org/abs/1508.05949v1 "For more than 80 years, the counterintuitive predictions of quantum theory have stimulated debate about the nature of reality. ... In the past decades, numerous ingenious Bell inequality tests have been reported. However, because of experimental limitations, all experiments to date required additional assumptions to obtain a contradiction with local realism, resulting in loopholes. Here we report on a Bell experiment that is free of any such additional assumption and thus directly tests the principles underlying Bell's inequality. ... This result rules out large classes of local realist theories, and paves the way for implementing device-independent quantum-secure communication and randomness certification." I'm not aware of any significant challenges to these studies.
- deleted 8y ago
  [deleted]
- thraway180306 8y ago
  It would help if these weren't all from the same single source: Zeilinger's Vienna group and friends. On the other hand formalism works seamlessly mathematically, which cannot be said of standard quantum mechanics. Even this year's Fields medalist Figalli has a paper on how good things are in Bohmian land.
  - jmcmichael 8y ago
    Fine, here's another from Ronald Hensen at Delft: Experimental loophole-free violation of a Bell inequality using entangled electron spins separated by 1.3 km 2015 https://arxiv.org/abs/1508.05949v1 https://arxiv.org/abs/1508.05949v1 "...This result rules out large classes of local realist theories, and paves the way for implementing device-independent quantum-secure communication and randomness certification. "
    - akvadrako 8y ago
      This isn't relevant because Bohm's theory isn't local. There are much stronger results like PBR ruling out a large class of non-local realist theories, but that also doesn't include pilot wave theory. No known experiment can rule it out because it's predictions equal those of Copenhagen.
    - thraway180306 8y ago
      This is something different. Zeilinger paints himself disproving realism alone and has a well known philosophical stance/bias here. Local realism testing here however is about being both local and realist, and pilot waves aren't local to begin with.
      - jmcmichael 8y ago
        Yeah, that makes sense. Do you have an example of Zeilinger's writing where he discusses his philosophical stance? Is a philosophical stance something you believe that a physicist shouldn't have?
lmm 8y ago
It's just many-worlds style wave-function realism with some extra epicycles on top. Treating the wavefunction as physically real is perfectly reasonable. Treating the wavefunction as physically real and then assuming there are also pseudoclassical particles on top adds nothing except appealing to the confused - "oh no, the particles aren't in a superposition, the particles are just ordinary classical particles... all of whose properties are determined by the pilot wave... which is in a superposition. Totally different."
- thraway180306 8y ago
  Not true, a lot of mathematical problems behave better (but other semiclassical approaches also exist). As for the epicycles comparison, it's actually apt. They could have given complex plane and Fourier analysis for free if they had a chance (not to mention Copernicus actually used more of them than Ptolemy)(which incidentally is also the case with Many-World-necessiated landscapes and parameter spaces - just as much additional layer but with additional problems that are, in contrast, untractable by current math).
  - deleted 8y ago
    [deleted]
- westoncb 8y ago
  > Treating the wavefunction as physically real is perfectly reasonable. What's your justification for that? I remember Arthur Eddington pointing out that it could be interpreted as modeling our limited knowledge of a quantum system just as well as its 'physical reality'. But there's obviously justification for the first one, while the second one appears to be a large unjustified leap.
  - lmm 8y ago
    > What's your justification for that? Occam's razor. The wavefunction is the simplest construct that explains our experimental results (it appears in every interpretation to some degree or another, certainly in pilot wave theory where it is the pilot wave), so it's simplest to assume it just is what's really happening. > I remember Arthur Eddington pointing out that it could be interpreted as modeling our limited knowledge of a quantum system just as well as its 'physical reality'. Hidden variable approaches are incompatible with our experimental results unless you introduce some seriously undesirable properties (e.g. nonlocality). I didn't say that wavefunction realism is the only reasonable approach, just that it's a reasonable approach. Pilot wave theory isn't - it introduces an extra layer of complexity justified by nothing more than human intuition (not even innate intuition, but the experience of classical mechanics).
tpfour 8y ago
I think you are abusing language here, probably not intentionally, and it distracts from the actual issue. You seem to understand the difference but for those who don't, here's a crucial distinction that's often overlooked by laypeople: The Schrödinger (Dirac) equation itself is deterministic. Given a wavefunction at time t=t0, you can calculate its evolution to time t=t1. What is indeterminate is the observation of the observable. The distribution of observations is entirely determined. Only the result of a single observation is indeterminate: in the limit of infinite measurements, you would get the probability distribution back which itself is determinate. The various "interpretations" concern themselves with what happens at the time of measurement. For example, the Copenhagen interpretation says that the wavefunction, which was evolving deterministically, mutates into a new wavefunction which itself evolves deterministically. This act of going from one to the other is considered indeterminate and is given the name of "collapse". However the dynamics of each wavefunction is entirely determinate.
tbabb 8y ago
De Broglie-Bohm is probably not the correct theory, since (if I am not mistaken) it's not reconcilable with relativity, and has a host of other problems which led its original proponents to abandon it. Copenhagen is also probably not correct, though it is still frustratingly mainstream. Copenhagen has the well known problem of lacking a physical definition of "observer", but it also has conflicts with delayed choice quantum eraser experiments (which suggest that the wavefunction never collapses), and contradictions that arise when you try to locate the proposed wave collapse in spacetime. The Everett many-worlds interpretation is gaining favor, and has none of the problems of the other two pictures. In the Everett view, scientists and experiments and instruments and universes are ensembles of particles like any other, and enter superpositions upon interacting with other systems in superposition. In a sense, every possible outcome of a quantum measurement actually happens in due proportion to the probabilities described by quantum mechanics, but upon becoming entangled with the experiment result, the different outcomes can no longer influence or measure each other. It is the most ontologically minimal theory, since it proposes no other events or laws beyond the already-known laws of quantum mechanics.
- effie 8y ago
  In the Everettian interpretation, experiments do not have results (!) and it is not clear what probability even means, much less how the Born rule and observed statistics arise. That's because it is not a theory about our world, but about an imagined world where the only things existing is the psi function. > every possible outcome of a quantum measurement actually happens in due proportion to the probabilities described by quantum mechanics This cannot work, because those probabilities are defined by a basis in Hilbert space and that basis is defined by details of the experiment, which does not actually happen in the Everettian view.
  - tbabb 8y ago
    I am not sure what you mean by "experiments do not have results." A measurement in Everett is the environment becoming entangled with the measured system, and a "result" is a particular basis of the combined wavefunction.
tntn 8y ago
I'm a big fan of epistemological interpretations of QM. Everything becomes far less mysterious when it is a theory of knowledge, IMO. Wavefunction collapse? No wonder it collapsed: it represents your knowledge and you just observed the system.
- retsibsi 8y ago
  That (to my complete layman's eye) seems reasonable, but is it really much more than shuffling labels around? It seems the 'deeper' mystery remains: what is going on at the fundamental level of reality? (Or, in other words, why do our observations have these properties?) Whether or not that question is answerable -- or even meaningful -- I think we'll always be driven to ask it.
kjeetgill 8y ago
I'm not super knowledgeable but I love this series, Looking Glass Universe, on the subject [0,1]. Specifically, she goes into some common but wrong beliefs about Bohemian Mechanics including that there is NO quantum weirdness. There is - it's called contextually. I don't know more than that. [0]: https://www.youtube.com/watch?v=r0plv_nIzsQ&t=2s https://www.youtube.com/watch?v=r0plv_nIzsQ&t=2s [1]: https://www.youtube.com/watch?v=Qz4CHI_W-TA https://www.youtube.com/watch?v=Qz4CHI_W-TA

MichaelAO 8y ago

Interesting interview with Basil Hiley (collaborator with David Bohm) on this topic: https://www.youtube.com/watch?v=wayQn0uVIvE https://www.youtube.com/watch?v=wayQn0uVIvE

macmac 8y ago

No.

amelius 8y ago
From the article: > To think that such a particle can think is so absurd, that I might give the answer “No” and have my talk over. However, (...)
Koshkin 8y ago
Well, for most definitions of 'think,' sure. But they can get excited - at least for some definitions of excitement.

panic 8y ago

I wonder what Schrödinger would have thought of the Free Will Theorem: https://arxiv.org/pdf/quant-ph/0604079.pdf https://arxiv.org/pdf/quant-ph/0604079.pdf

effie 8y ago
I think he would not like it. The theorem is underwhelming and uses misleading attention-seeking terminology. A more appropriate way to state it is, I think, this: if experiment settings violate determinism, its results have to violate determinism as well. To the author's credit, they say as much in the introduction themselves - "I saw you put the fish in".

Koshkin 8y ago

[Meta] A light, hard to read shade of gray. (Never understood why would anyone want to do that to the reader.)

stephengillie 8y ago
HN uses the same poor text contrast to highlight unpopular opinions.

edem 8y ago

From what I understand "seeing" is an active proccess, since it needs light. If we want to observe small things we need more precise light, which means more energy. The problem is not that small particles are somehow become aware when we observe, but the observation itself adds energy to the system, thus alters it. Is this correct?

stephengillie 8y ago
"Observing" means entangling with photons which have previously been entangled with the observed object. Thus, viewing an object means changing its state in such a way that you're temporarily also part of its state, forming an entropy gradient to gain energy/information from it.
- IAmGraydon 8y ago
  That is completely incorrect.

mentos 8y ago

If electrons are the lowest level of granularity when it comes to determining state in computers then maybe it is the same in the mind? I imagine a computer made of silicon with the trillions of grooves that the mind has in biological form would find itself to have a conscious just the same. Remove the silicon from the computer or biomass from the brain leaving just electrons behind and you would have a network I would argue gives rise to the seat of consciousness.

beautifulfreak 8y ago

I wonder if anyone here would be so kind as to explain Schrodinger's argument. I'm not grasping it. Is he making a fundamental point about the degrees of freedom an electron can have, delimiting ideas about how a brain can process thought with the help of self-willed electrons? Or is it confined to whether an electron itself can have thought. What point is he making in the debate about whether humans are automata? I'll read it again, but it's subtle and I might not understand quantum mechanics sufficiently to understand it.

Tomminn 8y ago
He's saying that just because the movements of particles are not predictable doesn't mean you all of a sudden get to claim "free will"-- the ability to somehow impose an arbitrary desire in the chain of causality between your sense experiences and your actions. In order for you to have "free will" in this classical sense, you'd have to control the "slit" the electrons "swerve" through. But you don't. They just act randomly. They're not the things that impose your will. Your will is still an illusion.