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Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

quantamagazine.org

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Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#81

Post by sampo »

beloch wrote: post #75
yoyohello13 wrote: post #39

Im fully willing to believe I just don’t “get it” but I took a pretty deep dive into quantum computing and the underlying mechanics and I kind of got the sense (with QC) that nobody really knows what they are talking about. I got this feeling so strongly that stopped studying the topic all together. I’m probably way off base and I’m probably missing some insights that I could get by going to school or something but t…

"I think I can safely say that nobody understands quantum mechanics." --Richard Feynman You're far from alone. Quantum physics is tricky because it frequently doesn't agree with our physical intuition. Humans are used to dealing with macroscopic objects. They surround us for our whole lives. Matter behaves in surprisingly different ways at the level of single quanta. Seemingly impossible things flop out of the math a…

> Quantum physics is tricky because it frequently doesn't agree with our physical intuition.

Quantum physics tricky for two separate reasons.

(i) The mathematical theory (Schrödinger equation, wave function, operators, probabilities) is solid and well-defined, but may feel unintuitive, as you say.

(ii) But quantum mechanics is also an incomplete theory. Even if you learn to be at peace with the unintuitive aspects of the mathematical theory, the measurement problem remains an unsolved problem.

"The Schrödinger equation describes quantum systems but does not describe their measurement."

"Quantum theory offers no dynamical description of the "collapse" of the wave function"

https://en.wikipedia.org/wiki/Wave_function_collapse#The_mea...

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#82

Post by Veedrac »

Maybe I am just out of my depth, but I don't understand what problem quantum Darwinism is solving. The Schrödinger equation already explains why observers seem to agree: the ones that don't are separated from each other.

This article is making some pilot-wave-like claim on top of quantum Darwinism that while the Schrödinger equation is real, all the 'real realness' exists in some pointer to a specific location inside it. Why does it do this? Where does this claim come from? At least collapse theories allow that the thing the Schrödinger equation is modelling is actually real up until the part God gets out his frustum culler.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#83

Post by diacritical »

kikokikokiko wrote: post #74
lukol wrote: post #69

Earlier quoted context omitted.

#1: You do not want randomness. You may believe you do until the Titanic crashes into your front yard and your significant vanishes into thin air. You want quite a lot of predictability, up to a degree where it might not even matter if things at the lowest level of existence are not perfectly deterministic. #2: What's so bad about thinking about life as an exciting rollercoaster ride? The tracks are laid but the ride…

If everything is deterministic, i.e. determined, there's no free will, so you/I are just a NPC. I prefer to live in a universe where my conscious decisions matter, or at least can't be predicted beforehand.

Randomness doesn't imply free will. What if you/I are NPCs that just roll the dice before doing something? It's not you that chose the outcome, it's the dice, i.e. the laws of physics.

I don't know how free will could actually work with any kind of universe governed by a set of laws, whether they include randomness or not. So I don't believe in it, but of course in my day to day life I act as if it exists.

Yet I don't know how qualia or subjective experiences could actually work with any kind of universe governed by a set of laws, whether they include randomness or not. But I believe I have this subjective view of the world that doesn't seem to be explainable with a set of equations.

So it's weird. At least philosophy and science agree that.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#85

Post by firebot »

kikokikokiko wrote: post #74
lukol wrote: post #69

Earlier quoted context omitted.

#1: You do not want randomness. You may believe you do until the Titanic crashes into your front yard and your significant vanishes into thin air. You want quite a lot of predictability, up to a degree where it might not even matter if things at the lowest level of existence are not perfectly deterministic. #2: What's so bad about thinking about life as an exciting rollercoaster ride? The tracks are laid but the ride…

If everything is deterministic, i.e. determined, there's no free will, so you/I are just a NPC. I prefer to live in a universe where my conscious decisions matter, or at least can't be predicted beforehand.

Compatibleism is when you have both free will and determinism.

What you seem to prefer is libertarianism.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#86

Post by sbuttgereit »

ur-whale wrote: post #68
suhputt wrote: post #64

Earlier quoted context omitted.

might make sense to link to the actual material you're referring to

> Highly recommend looking at Jacob Barandes’ formulation of quantum mechanics as non-Markovian stochastic processes. seconded >might make sense to link to the actual material you're referring to https://www.youtube.com/watch?v=sshJyD0aWXg In a fews sentences: the evolution of a physical system (quantum and classical) can very successfully be modeled as a stochastic process, and ... 1. state of the system is a real-v…

This was a good discussion on the topics involved as well; between Jacob Barandes & Tim Maudlin. Though I don't recommend watching this without first getting some familiarity with Barandes's ideas... while there's some explanatory dialog in this video I'm posting, mostly is a discussion. It's nice to see the ideas (politely) challenged and answered.

https://www.youtube.com/watch?v=8xPvxAdmhKM

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#89

Post by B1FF_PSUVM »

gerdesj wrote: post #55
superposeur wrote: post #47

Earlier quoted context omitted.

These debates over the interpretation of Quantum Mechanics (i.e. what ultimately happens when a “measurement” takes place) are important but don’t bear on the effectiveness of quantum computing. Regardless of your favorite interpretation (almost) everyone agrees that quantum computers should work and be able to do things classical computers cannot.

Credo.

... quia absurdum est?

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#90

Post by diacritical »

A_D_E_P_T wrote: post #24
Sharlin wrote: post #23

Earlier quoted context omitted.

So you say that the hard problem of consciousness is explained by the fact that we appear to be conscious?

The kneejerk response would be: Are you not conscious at this present moment? If we were to modulate your spatiotemporal senses with drugs or a lobotomy, do you doubt that you would be very differently conscious, or perhaps entirely unconscious? I mean, there is a credible first-person answer to that question of yours, which each man can answer for himself. But considered more seriously, the "hard problem" is an arti…

I'm not a dualist or anything. I'm in the "it's weird and I have no idea what the answer is" camp. And yes, I've read Dennett. I'm trying to understand your views. Lots of questions follow, but don't feel like I'm barraging you unnecessarily. Just trying to figure out your view with what seem to me like interesting questions that I myself can't really answer.

I'm using "consciousness", "subjective experiences", "senses" and "qualia" as synonyms here, but if you see a difference, please mention it. Obviously "consciousness" has many definitions that have nothing to do with the "hard problem of consciousness", so I'm using it in this sense here. I'll use "qualia" as it's the word that relates most to the hard problem of consciousness. You can substitute it with "sense"/"senses" if you like.

1. Do you view qualia as an emergent property? Of what exactly? What is a self-modeling system? Is a human one? Where would the boundaries be; would they even be defined? The human body or the brain only or the nervous system? Or whatever neurons activate when a certain thing happens, like seeing blue or feeling pain? What about animals - pigs, dogs, rats, snails, ants, bacteria? What about AI, current and theoretical?

2. Could there be a set of minimal self-modelling systems in some abstract space that are the boundary of what has qualia and what doesn't? Like, these 1000000 neurons arranged like that qualify, but if you take 1 out, they don't? Or is it a fuzzy boundary somehow?

3. What kind of statements could be made about the qualia of yourself and of others? Not sure what kind of answer I'm looking for, but how objective or truthful would those statements be? Maybe "qualia is nothing really, we only have the set of equations that govern physics and everything else is an abstraction"? Like an apple isn't anything really, it's just a badly defined set of atoms and energy. There is no "apple" or "chair". Or is it something else?

4. What are your views on meta-ethics and ethics in general? Should we care about it at all?

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