Right, guardians dispatched, onto the boss :) There’s lots of really interesting stuff here to follow up, some of which will take me a very long time. All of

Right, guardians dispatched, onto the boss :) There’s lots of really interesting stuff here to follow up, some of which will take me a very long time. All of it is appreciated as I haven’t yet had the opportunity to discuss the subject with somebody who truly has a handle on the subject - at least not since the optional first year physics module I took as part of my CS degree 17 years ago, and that didn’t go this far. In no particular order… > I would avoid trying to push your game as a pedagogical learning tool unless it's been thoroughly vetted by actual physicists Noted, though vetting is exactly what I’m trying to make a start on here :) Your comments on the learning process are interesting and don’t square with my own experience, though perhaps they would if I were formally taught. I might scale them back. While we’re talking about vetting, if you’d like to be credited for your efforts towards that, by real name or HN handle, please let me know as I feel it would only be fair to add an acknowledgement. >Gauge symmetry isn't the independence of the global phase---it's the independence of a spacetime-dependent phase. I don’t quite follow what the latter means, but is it correct to say that independence of global absolute phase arises from gauge symmetry? >That's exactly the opposite of what the Schrodinger equation says! Noted and understood. I should replace “can’t exist” with “has low probability” and modify accordingly. >If you can find a way to simulate an arbitrarily-sized quantum computer with a reasonable amount of computing, you will get famous. A few particles should be possible but it won't scale well. Yup. A few particles was what I had in mind. >> Nuclear forces arise when … >Oy. This is wrong. Excellent advice, thanks for the heads up: I’ll cut the entire footnote. Are nuclear forces getting beyond QM then – into QFT? I would love to go on and learn that but haven’t got there yet. >> Until that question is answered, then we can’t rule out the possibility that consciousness does have something to do with it. >Are you sure you only read Feynman? This is an extreme fringe position. I don't know any physicists who actually holds this position, unless they're trying to get on TV. >No. Decoherence is the thing that lets you avoid the need to collapse at all. >This is the claim of the Many Worlds interpretation With interpretations of QM I think we’re getting more into philosophy than physics, until the day comes that we get different predictions from any of them. Somehow this makes me feel qualified to argue with a nuclear physicist... I may be discussing a fringe position, but am I right in thinking your counterargument relies on invoking many worlds, which isn’t mainstream either? To summarize the popular interpretations - Copenhagen is mainstream but doesn’t explain collapse - Many worlds is quite popular but possibly the least parsimonious theory in the entire history of science - Pilot wave theory holds promise as it doesn’t need collapse, it isn’t mainstream though seems to be gaining popularity at the moment So at the moment I’d say there is still room for a consciousness based interpretation. I’m a former AI researcher btw, I used to take the strong AI consciousness-as-emergence position but I no longer think that explanation cuts the mustard. At the present state of science I think all we can say about consciousness is “there is some very big important process going on and we don’t have the first clue what, where and how”... as such I don’t think it’s scientific to completely rule out the possibility that consciousness is involved in collapse as the latter is a process we haven’t adequately explained yet either. Presumably most physicists steer clear of this as consciousness is so far beyond where science is now that they’d rather (quite sensibly) not speculate, lest they be remembered as the Victorian engineer who thought life came from electricity. My aim is to discuss not support that view by the way – I think a newcomer to the subject would naturally be curious about why some people think consciousness is involved. Still, until there’s experimental evidence I’m hedging my bets. Anyway enough pub chat! Finally I’d be interested to know your take on leni536’s point about uncertainty further down this thread? That seems to be an unresolved technical discussion to me.