I like this discussion because it does not try to hide the fact that the interplay of the observer and the wave function in quantum mechanics is a fundamental unresolved question in physics.
Are observers central to physics, or are they more accurately framed as bystanders to and byproducts of phenomena that exist independently of consciousness? In this interview from the long-running series Closer to Truth, Bernard Carr, an emeritus professor of mathematics and astronomy at Queen Mary University of London, traverses the double-slit experiment, the fine-tuning argument and more to explore what significance, if any, first-person observation holds in the realm of fundamental physics. In his conversation with the US presenter Robert Lawrence Kuhn, he doesn’t adopt a personal stance. Instead, he considers these persistent questions through a contemporary frame, assessing how discussions around them have evolved and where they stand among physicists today.
Well, that was vague. I’m sure Carr has done sterling work in his chosen academic field, but I’m a bit leery when he talks about consciousness.
https://psi-encyclopedia.spr.ac.uk/articles/bernard-j-carr#:~:text=Bernard%20Carr%20(b%201949)%20is,normal%20and%20paranormal%20mental%20experiences.
it might be outside your wheelhouse -- i know advanced sciences are so specialized it might not be something you ever worked with -- but i’d be more interested in your take on this phenomenon than in that of a guy with unknown atheist-skeptic bona fides. this issue opens the door to mysticism so easily i really feel it’s better to bring non-mystic prejudice to the table than not.
Bébé Mélange,
Let me think about how best to formulate my own views on this topic and post something in a few days.
thanks! i hope i’ll understand them, heh.
Haven’t watched the video yet, but my understanding on this is basically as follows.
First, most physicists are really uncomfortable with doing anything that places special emphasis on consciousness. Quite aside from all the ‘woo’-y aspects of it, this runs up against one of the foundational principles of scientific investigation, that there is nothing special about our particular time or place as far as the baic rules are concerned. (If the rules change, tat means they’re actually just special instances of deeper rules.) The Anthropic Principle is essentially a null statement in its weak form (the universe is as it is because if it weren’t we wouldn’t be here to wonder why) or an unfalsifiable assumption that may help you with statistical analysis but which inherently can’t help you with proofs, because our universe might just be one of the outliers.
Second, one of the more accepted interpretations on quantum theory these days is a ‘coherence’ model. Basically, there is no single magical moment of ‘collapse’ by observation, because the observer is also composed of quantum systems. Instead what happens is that as the original ‘unobserved’ quantum state starts interacting with and getting entangled with other quantum states around it, and thus entangled by proxy with every other state that those were, there effectively becomes a point at which the quantum state is entangled with so many other states that it becomes a fixed part of a macroscopic system, and that state can no longer be uncertain on its own without every other state it’s entangled with also being uncertain.
Given that there’s evidence that quantum entanglement may also be associated with entropy, ‘quantum collapse’ may be essentially the second law of thermodynamics on the quantum scale.
jenorafeuer @5:
No surprise there. What the fuck is ‘consciousness’?.
Right. ‘Collapse’ was always (whether recognized or not) a placeholder for ‘interaction with the environment’.
@Rob Grigjanis:
Right. Some of my thinking on this comes from having read Nick Herbert’s book Quantum Reality back when I was in university; the book, admittedly, is forty years old now. But he went through several of the different interpretations of quantum theory, along with pointing out that all of them were at least broadly consistent with the actual mathematics of quantum theory, so designing an experiment that would actually be able to decide between them was difficult. He also went into the math of Bell’s Inequality and how it predicted probabilities that just fundamentally did not mesh with intuition, basically that Bell’s Inequality made any sort of local hidden variable interpretation impossible. He mentioned eight interpretations, and while I don’t have the book to hand some of them were:
-- Basic Copenhagen Interpretation: “Measurement (hand-waving here) causes collapse”
-- Extreme Copenhagen Interpretation: “Nothing can be said to exist unless it is measured”
-- Von Neumann Interpretation: “Consciousness causes collapse”
-- Bohm ‘Pilot Wave’ Interpretation: “There is no collapse because there is no uncertainty) (but this needs FTL communication).”
-- Many-Worlds Interpretation: “There is no collapse, only selection of which possible outcome happened for the observer.”
-- Quantum Logic: “Bell’s Inequality only looks like a paradox because we’re expecting the quantum world to abide by macroscopic statistics, and once we find the real rules it will all make more sense.”
I forget what the other two were.
In a sense ‘coherency’ is another variant of the Copenhagen Interpretation but with an actual attempt at a definition of what a ‘measurement’ is, and an actual rationale of why quantum and macroscopic states are different and a justification of why things will cross the line. Interestingly there are actually possible experiments for some of this, as coherency suggests that the ‘collapse’ is not an instantaneous process and there should be intermediate states. It’s just that those states won’t last long.
Yeah . . I’d prefer to see this discussion done by someone who isn’t a blatant supernaturalist. I watched several episodes of this show back in the day, and IMO, it should be titled “Closer To Woo”.
Looks like this interview is taking place in a nice pub. Which gets me thinking the conversation needs more beer. And/or more weed…
@Rob
All this time , I didnt realize you were a beta version of ChatGPT .
🙂