Are the weirdnesses of QM still regarded as mysteries to be resolved?

[Alfred001]

All the typical weirdnesses of QM - the double slit experiment, observation collapsing the wave function etc. - are they still regarded as mysteries that need to be resolved, or is the view now that that's just how the universe is and there is no explanation beyond that?

[Eise]

Depends on what you think is weird. If 'weird' means 'completely against our deepest intuitions', then some weirdnesses will remain forever. If you mean with 'weird' that we have no explanation, then my educated guess is that the collapse of the wave function is an unresolved weirdness.

To give an example of 'weird, but explained' belongs in my opinion entanglement: the mathematics of QM is clear that entanglement exists. So we have an explanation, but it is strongly against our daily intuitions. Except that at the bottom of entanglement also lies a collapse of the wave function... 

If something that is not (yet?) explained is a mystery is another question. If you see some process that you do not understand, but it is repeatable, and you can even base technology on it, is this a mystery? Or is it just natural, but (still?) unexplainable.

[taeto]

2 hours ago, Alfred001 said:

All the typical weirdnesses of QM - the double slit experiment, observation collapsing the wave function etc. - are they still regarded as mysteries that need to be resolved, or is the view now that that's just how the universe is and there is no explanation beyond that?

Isn't it the other way around? What we observe in nature is the weird looking stuff. And QM is the, or at least one, explanation for it? I do not see how you can take the observations that we make about the universe to not reasonably represent how the universe is.  

[swansont]

“Why is the universe the way it is” veers pretty quickly into metaphysics

[QuantumT]

10 hours ago, Alfred001 said:

All the typical weirdnesses of QM - the double slit experiment, observation collapsing the wave function etc. - are they still regarded as mysteries that need to be resolved, or is the view now that that's just how the universe is and there is no explanation beyond that?

I think it depends on the attitude of the scientist. Scientists are people like everybody else, and they have likes and dislikes.
Some dislike mysteries, that leave room for woo interpretations, so they prefer to cut the BS and simply say "that's just how nature is".
I, myself, am the more stubborn kind, and refuse to give up on achieving a reasonable explanation.

[beecee]

Weird or not, the prime issue is that we see and know this quantum weirdness is actually the norm.

[Mordred]

Well from a personal view, I find that the quantum regime isn't weird once you remove classical viewpoints. Entanglements and wavefunction collapses obviously involve probability functions but the mathematics are similar to statistical mechanics.

 

[swansont]

11 hours ago, Mordred said:

Well from a personal view, I find that the quantum regime isn't weird once you remove classical viewpoints. Entanglements and wavefunction collapses obviously involve probability functions but the mathematics are similar to statistical mechanics.

 

I agree with this. A lot of how we present QM and its weirdness is because we use classical behavior as a bridge (e.g. Bohr atom, tunneling, wave-particle duality), which I think ends up being confusing, since some people try to continue imposing classical behavior on quantum systems. 

 

[dimreepr]

18 hours ago, QuantumT said:

I, myself, am the more stubborn kind, and refuse to give up on achieving a reasonable explanation.

It's reasonable to assume reality will continue to baffle a reasonable explanation...

[QuantumT]

3 hours ago, dimreepr said:

It's reasonable to assume reality will continue to baffle a reasonable explanation...

Just like there's a logical reason for Brownian motion, I firmly believe there's a logical reason for duality. We just need to find it (or gain consensus for an existing idea).

[StringJunky]

1 hour ago, QuantumT said:

Just like there's a logical reason for Brownian motion, I firmly believe there's a logical reason for duality. We just need to find it (or gain consensus for an existing idea).

You would probably be better off letting go of that belief because, as swansont said earlier, it's bringing classical ideas into the quantum domain. So, AFAIK, duality is only a mystery when you try to use classical descriptions to describe quantum phenomena.

Edited March 5, 2020 by StringJunky

[Strange]

3 hours ago, QuantumT said:

Just like there's a logical reason for Brownian motion, I firmly believe there's a logical reason for duality. We just need to find it (or gain consensus for an existing idea).

Done. The "logical reason" is quantisation.

Pretty much all the counter-intuitive ("mysterious") quantum behaviour is just a consequence of the quantisation of the wave and field equations.

BTW: slightly off-topic, but relevant, there was a great BBC radio program on Paul Dirac this morning: https://www.bbc.co.uk/programmes/m000fw0p

[QuantumT]

2 hours ago, StringJunky said:

You would probably be better off letting go of that belief because, as swansont said earlier, it's bringing classical ideas into the quantum domain. So, AFAIK, duality is only a mystery when you try to use classical descriptions to describe quantum phenomena.

Well, I think it can be de-mystified with commonsense reasoning 😉
Only problem is the rejection that naturally follows, when ones paradigm is challenged.

 

1 hour ago, Strange said:

Done. The "logical reason" is quantisation.

Pretty much all the counter-intuitive ("mysterious") quantum behaviour is just a consequence of the quantisation of the wave and field equations.

How does quantisation explain the observer effect?
If you ask me, it is much better and simpler explained as a GPU response.

 

But guys, don't mind me. I know you don't agree with me, and I'm not trying to convince you. The subject of this thread was begging me to throw it in. I'll hush now 😁

[Strange]

35 minutes ago, QuantumT said:

How does quantisation explain the observer effect?

The observer effect is a classical phenomenon, so I'm not sure it is relevant.

36 minutes ago, QuantumT said:

If you ask me, it is much better and simpler explained as a GPU response.

What is a "GPU response"?

36 minutes ago, QuantumT said:

Well, I think it can be de-mystified with commonsense reasoning

Not sure how you can use common sense to explain something that is counter-intuitive (i.e. counter to common sense). If that were the case, it wouldn't be considered "mysterious".

(Having grown up with these concepts, I'm not sure why they are considered so mysterious, anyway. I mean, come on guys, we have known about this for 100 years. It can't still be surprising.)

[druS]

I had thought that said there was increasingly a will to investigate quantum foundations with broader thinking than the Copenhagen interpretation. Everett inspired many worlds interpretation has followers,  there is even some work, I understand, on pilot-wave interpretation. I'm unsure on what developments in quantum holography and quantum information provide but it is further work in the area.

Clearly the body of knowledge that is quantum mechanics, remains highly precise and successful, but this hasn't meant that quantum foundations are not being further considered. Examples:

• Einstein's Unfinished Revolution, The search for what lies beyond the quantum: Lee Smolin
• What Is Real? The unfinished quest for the meaning of quantum physiscs: Adam Beckler Note to the OP - this is an easily read and digested run through the topic.
• Something Deeply Hidden, Quantum worlds and the emergence of spacetime: Sean Carroll [Admit to having not read this yet, though I have listened to his podcasts and most of his available lectures]

As an interested non-expert (I am working on it!) it appears that there is plenty happening in an areas previously considered effectively settled.

Edited March 5, 2020 by druS

[MigL]

Weirdness is relative.

( hey, did I just propose a new unification ( QM and GR ) strategy ?  )

[Mordred]

QM weirdness is already treated relative via QFT lol. 

 Seriously though many place too much store in quantum interpretations. While they are useful tools what is fundamentally important is that we can accurately model the dynamics we can measure in the quantum regime.The problem lies with the region we can never potentially measure as their is insufficient action. Ie the propogator portion of a Feymann path integral. Some of the interpretations such as the Bohmian attempts to stick to the particle view while others the particle is a wavefunction. Yet the pointlike properties can be described by a wavefunction. There will always be contention between these two views.

Entanglement and hidden variables are one source of contention between the two views. Yet often both forget that the act of entanglement itself makes hidden variables unnecessary. You can start establishing your correlation function with the rest of the probability involving the experimental apparatus.

 

 

Edited March 6, 2020 by Mordred

[swansont]

18 hours ago, QuantumT said:

Well, I think it can be de-mystified with commonsense reasoning 😉
Only problem is the rejection that naturally follows, when ones paradigm is challenged.

We physicists do tend to want experimental evidence as confirmation, and "commonsense reasoning" doesn't qualify.

 

 

17 hours ago, druS said:

I had thought that said there was increasingly a will to investigate quantum foundations with broader thinking than the Copenhagen interpretation. Everett inspired many worlds interpretation has followers,  there is even some work, I understand, on pilot-wave interpretation. I'm unsure on what developments in quantum holography and quantum information provide but it is further work in the area.

Clearly the body of knowledge that is quantum mechanics, remains highly precise and successful, but this hasn't meant that quantum foundations are not being further considered. Examples:

• Einstein's Unfinished Revolution, The search for what lies beyond the quantum: Lee Smolin
• What Is Real? The unfinished quest for the meaning of quantum physiscs: Adam Beckler Note to the OP - this is an easily read and digested run through the topic.
• Something Deeply Hidden, Quantum worlds and the emergence of spacetime: Sean Carroll [Admit to having not read this yet, though I have listened to his podcasts and most of his available lectures]

As an interested non-expert (I am working on it!) it appears that there is plenty happening in an areas previously considered effectively settled.

Have investigations into quantum foundations resulted in any new physics?

[MigL]

On my birthdate...

No, seriously ( and back to the OP ), the only reason for quantum 'weirdness' is that QM involves a paradigm ( every chance I get to use that word ) shift in the way we view reality. While the classical view is deterministic, the quantum view is probabilistic.

It's a difficult shift in viewpoint when we first encounter QM.
( but you get used to it )

[Phi for All]

!

Moderator Note

Hijack re classical questions has been split off to here.

 

[Alex Caledin]

Hello everyone!

Is it possible simply to accept the most usual QM boldly and straightforwardly like this,

All the Nature's observable physical properties are the outcome of the universe wavefunction collapse;

we cannot - even in principle - know (scientifically) how exactly that universal collapse comes - but it seems coming according to the Born Rule so as to maintain the apparent Nature's statistical "naturalness";

-  that's why the usual QM is FAPP-applicable, every prepared laboratory wavefunction being a "branch" of that universal collapsing wavefunction.

(So every textbook quantum system is a "toy universe", its properties being formed by the abstract collapse.)

Edited March 21, 2020 by Alex Caledin

[dimreepr]

1 hour ago, Alex Caledin said:

Hello everyone!

Is it possible simply to accept the most usual QM boldly and straightforwardly like this,

All the Nature's observable physical properties are the outcome of the universe wavefunction collapse;

we cannot - even in principle - know (scientifically) how exactly that universal collapse comes - but it seems coming according to the Born Rule so as to maintain the apparent Nature's statistical "naturalness";

-  that's why the usual QM is FAPP-applicable, every prepared laboratory wavefunction being a "branch" of that universal collapsing wavefunction.

(So every textbook quantum system is a "toy universe", its properties being formed by the abstract collapse.)

So we give up trying? That doesn't seem very scientific, besides acceptance belongs, more, in the spirit realm.

The way I understand it, as a laymen (so certainly wrong but it may help my brethren), is that it's like a bell curve squared; in how the quantum world relates to our world. 

[Alex Caledin]

On 3/21/2020 at 5:04 PM, dimreepr said:

So we give up trying? That doesn't seem very scientific ...

- But look, it was always like that! Before the QM, the classical motion was according to the least action - and no one tried to find out how exactly Nature was finding that least action way to move things - so it was quite satisfactory.

Edited March 25, 2020 by Alex Caledin

[swansont]

1 minute ago, Alex Caledin said:

- But look, it was always like that! Before the QM, the classical motion was according to the least action - and no one tried to find out how exactly Nature was finding that least action way to move things - so it was quite satisfactory.

I'm confident that some people tried to find out. They appear to have not succeeded.

[dimreepr]

3 minutes ago, Alex Caledin said:

- But it was always like that! Before the QM, the classical motion was according to the least action - and no one tried to find out how exactly Nature was finding that least action way to move things - so it was quite satisfactory.

How far back are you going?