B Why is Quantum Physics so Strange?

[Stavros Kiri]

The second is a definition so how can it be a law?

Definition of the force ... you mean. I prefer the approaches that take 'forces' as primitives, or measured facts, and then it is a law ... . [Isn't that what we do in practice, e.g. in homeworks? (e.g. "there is a total force F acting from a spring on a mass m ... find velocity over time ...") ...]
But let's not get more off topic, although I am sure there is paradigm analogies in QM ...

 

[Stavros Kiri]

The true basis of classical mechanics is the principle of least action (plus symmetry of which the principle of relativity is an example) which follows from QM (the principle of least action that is - symmetry is everywhere in modern physics).

Now the interesting twist is its one of the true basis of QM as well (ie all our theories can be expressed that way)-

+ i.e. cf. the Feynman path integral formuation of QM, + e.g. see
https://www.physicsforums.com/threa...on-for-principle-of-stationary-action.874921/

 

[bhobba]

Is it? What about truth? What's the world's favour? That's still open ...

Well of course. Since by definition truth is how things actually are and all interpretations are equally valid we don't know the truth. But we don't know the truth about many many things - that's nothing new.

But here is a suggestion. We do know the truth of quite a few things and some of those things like symmetry and it's role in physics is downright startling - instead of worrying about things that as Feynman says sends you down a hole no one escapes from, study them. Very very few people have been able to make fundamental contributions to the foundations of QM and most of those that have, like Bell, were truly great physicists.

Thanks
Bill

 

[Stavros Kiri]

Well of course. Since by definition truth is how things actually are and all interpretations are equally valid we don't know the truth. But we don't know the truth about many many things - that's nothing new.

But here is a suggestion. We do know the truth of quite a few things and some of those things like symmetry and it's role in physics is downright startling - instead of worrying about things that as Feynman says sends you down a hole no one escapes from, study them. Very very few people have been able to make fundamental contributions to the foundations of QM and most of those that have, like Bell, were truly great physicists.

Thanks
Bill

But until we know the full true picture, "anything is possible" ..., and we shouldn't jump to conclusions (e.g. about QM ...) ...

 

[rootone]

the reason why quantum physics is strange is because it is about probability

 

[bhobba]

the reason why quantum physics is strange is because it is about probability

I think an Actuary might dispute that.

Really strange is a rather personal thing - what is strange to some person is obvious to another. You won't get anywhere with questions like why is QM so strange because it degenerates into opinions on what's strange - not facts.

It is as it is. I have read things like the following:
http://www.scottaaronson.com/democritus/lec9.html

To me that view makes it actually rather ho hum rather than strange. But that's me - others will likely disagree which is why this type of discussion won't actually get anywhere.

Thanks
Bill

 

[rootone]

Yeah Bill, but a lot of people don't like the idea of being a statistical casualty,
anyway thanks for that link.
less than 0% chance of snow tomorrow is interesting, probably true,but you never know

 

[markjoel]

Hmm, denying the physics community "dirty little secret" is, I hope, over. If reality is, at best, tentative in the atomic realm, how does that translate into the macro world? Am I living in a pseudo existence? Big things should be made of smaller things and so on down the line. Are we looking through rose colored glasses and seeing our own mind's perception of reality which may not even exist?

 

[Zafa Pi]

I want to be a quantum physicist as a career because i absolutely love the mystery behind certain principles in quantum physics. Especially things like the quantum eraser experiment. I am wondering if there is a reason that quantum mechanics has very weird principles that seem to defy logic, like quantum tunneling.

Rest assured QM is weird, gravity is weird, some of the writers in this thread are weird. Don't be swayed by the jaded who like to proclaim that their knowledge eliminates weirdness. Reality provides unending fascination and physics is the most fundamental line of inquiry, go for it. If you're ever strapped for $ at worst there will always be war work or Wall Street. If the incoming administration sticks around just start an article with "QM proves there is no global warming ... climate is in a state of superposition, simultaneously too hot and too cold; be careful not to observe it otherwise the climate will collapse in Denmark", instant funding.

 

[PeterDonis]

This topic has been discussed enough. Thread closed.