Quantum Physics discussion thread

[4472TJ]

Ok I'll put it out here, I am mad for quantum physics. It is such a new(ish) interesting and useful branch of science that it has me hooked. I love working on new ideas that will change the world of science, and I'm wondering, who else likes this subject and is as mad as me to like it!

[Dafni]

Cheers man, my job is closely related to quantum physics. For almost 20 years now I am growing crystals that are used in fundamental research, materials with interesting optical or magnetic properties. Either way the theories behind it are quantum related. The crystals may end up in simple laser labs in some university, or all the way up to big neutron scattering facilities. Often involving quite extreme conditions, low temperatures, high magnetic fields etc.

Myself I never studied physics, so my theoretical knowledge is very limited, but you pick up stuff over the years. And its super nice to contribute physical samples to a field otherwise dominated by so much theory. For example one of my materials was used to proof a magnetic phase state that was only predicted by theories. Even though I dont hold a degree myself, my name appears now on quite a few papers related to the topic, my contribution being quite essential to the whole process.

What about you @4472TJ? You pursue a scientific career?

[p1t1o]

Quantum physics is not necessary only to do with esoteric "quantum weirdness", I studied chemistry for my degree and it basically permeates the entire field. 1 entire third of my degree was "physical chemistry" which is a bit of a weird way to say "the physics of chemistry" and its just pages and pages of the maths you need to describe normal chemical interactions. Take the simplest example of two atoms forming a bond, quantum physics is how you explain how it works, or make prediction on how it will work.

Im not sure if I actually "like" it, theres too much maths.

But if the weirdness is your bag, this is one of my favorite examples:

https://en.wikipedia.org/wiki/Elitzur–Vaidman_bomb_tester

[4472TJ]

2 hours ago, Dafni said:

What about you @4472TJ? You pursue a scientific career?

Not yet. But soon...

 

 

1 hour ago, p1t1o said:

Quantum physics is not necessary only to do with esoteric "quantum weirdness", I studied chemistry for my degree and it basically permeates the entire field. 1 entire third of my degree was "physical chemistry" which is a bit of a weird way to say "the physics of chemistry" and its just pages and pages of the maths you need to describe normal chemical interactions. Take the simplest example of two atoms forming a bond, quantum physics is how you explain how it works, or make prediction on how it will work.

Im not sure if I actually "like" it, theres too much maths.

But if the weirdness is your bag, this is one of my favorite examples:

https://en.wikipedia.org/wiki/Elitzur–Vaidman_bomb_tester

Cool!

 

There was once a physicist that said, "If when you hear about quantum physics and you are not confused and amazed, you haven't really understood it"

There was also another person who said that, "Quantum physics confuses everyone, half the time scientists don't know what they are doing!"

Edited February 20, 2019 by 4472TJ

[p1t1o]

58 minutes ago, 4472TJ said:

There was once a physicist that said, "If when you hear about quantum physics and you are not confused and amazed, you haven't really understood it"

There was also another person who said that, "Quantum physics confuses everyone, half the time scientists don't know what they are doing!"

lol yes, the one I have heard is "If you think you understand quantum physics, you definitely dont."

I mean, some of the equations you use for various things, you can follow. Sodium and Chloride make a crystal, we know this, and the equations agree nicely.

But when it comes to the fuzzy edges, or places where the hypotheses are less well developed (like quantum gravity for example) things start to get weird very fast.

Dont get me started on quantum entanglement....

No, I mean DONT. I dont want to think about it!!

Edited February 20, 2019 by p1t1o

[4472TJ]

Well 

2 hours ago, p1t1o said:

Don't get me started on quantum entanglement....

No, I mean DONT. I dont want to think about it!!

Its a terrible shame that I do. And I know only a few things about it so all the more information the better...

[Gargamel]

Moved to S&S forum, as I know this crowd, and while it may be a light discussion of QM and possible career paths associated with it, this will very shortly turn in to an argument about which quark gluon interaction is better. 

[Cunjo Carl]

Glad you've found your calling, @4472TJ!

Like the others, I work with quantum mechanics, but not on it. It's an art that requires some serious dedication, so it's good to see that you seem to have that in spades! I think you'll have no troubles finding applications for those skills with quantum mechanics permeating physics and chemistry and quantum computing itself hanging on the horizon.

I'm crazy for pretty much all of the sciences: physical, biological, and all the squishy ones inbetween...  it spreads me a little thin, but I managed to scratch a career out of being a generalist, so I'll consider myself a happy person for it! As for interesting tidbits of QM, I'll add a few of my favorites to the mix:

The Quantum Zeno effect can be summed up as 'a watched pot never boils'. If you stare at an excited particle long enough and hard enough, it can never actually decay! Thanks, QM. Never Change This is often used in conjunction with the bomb testers mentioned earlier by @p1t1o to make sure the light never travels along the bomb's path so they don't ever actually detonate the bomb despite measuring it ... and it's been verified in experiment . In other words, it can force (to a high probability) light to travel along a certain path when it hits a half-silvered mirror, despite the superposition still travelling along both paths. This was first discussed by Kwait et al. (if you're on a campus maybe try checking their paper) P. Kwiatet al., “Interaction-Free Measurement,”Phys. Rev. Lett.,1995. But Vaidman actually talks about it in this overview on page 16.
https://www.tau.ac.il/~vaidman/lvhp/m87.pdf

 

In regards to the "no one understands quantum mechanics" quote, I think it's important to note that the person who said that, Feynman, did his best on his own alternative interpretation to QM! It turned out to not pan out quite how he expected, but it was awesome he tried, before settling back to a variation on the standard interpretation. Here's a list of QM quotes, including my favorite, a cheeky synopsis of the standard Copenhagen interpretation: "Shut up and calculate!" 
http://www.users.csbsju.edu/~frioux/quantumqts.html

This paper provides a wonderful perspective of how our understanding of QM has evolved, by providing a modern day view on a historical discussion/argument from Feynman over the quantization of gravity. https://arxiv.org/ftp/arxiv/papers/0804/0804.3348.pdf

And finally, I'll take this chance to plug one of my favorite youtube channels, along with my favorite alternative interpretation to the standard Copenhagen QM. Many more theoretical physicists think it's wrong than right, so take it with a grain of salt! Still, with any science, it's an important thing to consider why we believe what we believe and what the alternatives might be.

 

Edited February 21, 2019 by Cunjo Carl
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