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Physicists demonstrate new way to violate local causality

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21–30 of 74 posts

Re: Physicists demonstrate new way to violate local causality

#21

Going meta here, speaking from the perspective of a software engineer with a great interest for physics. There are a lot of terms I do not fully understand in this article. Can you recommend an application that would allow me to select for example the words "distant particles can be correlated in ways that are impossible for classical objects" and find out what lead to that discovery? Or what does "Bell inequality" r…

> what does "Bell inequality" really mean

Some stuff is just hard to understand. You can make analogies, like talking about two people hiding a colored ball in their hand and one of them showing it later, but these are not truly helpful in really understanding the issue. For that you need a bit of math.

One physicist explained this really nicely, saying that because we live in the macroscopic world we have a certain kind of experience of it, and our gut feelings and intuitions are just wrong when applied to the microscopic world, and using math is just a way of avoiding these misconceptions, and after a while of doing that you will get a new "math intuition" of physics.

Re: Physicists demonstrate new way to violate local causality

#22
post #15

Earlier quoted context omitted.

> Can you recommend an application that would allow me to select for example the words "distant particles can be correlated in ways that are impossible for classical objects" and find out what lead to that discovery? Or what does "Bell inequality" really mean? If not, are there recommended methods of understanding articles better? Venkman: Ray, pretend for a moment that I don't know anything about metallurgy, enginee…

Can you recommend an entry level Physics/QM book?

The Feynman Lectures on Physics are not half bad.

Re: Physicists demonstrate new way to violate local causality

#23
post #15

Earlier quoted context omitted.

> Can you recommend an application that would allow me to select for example the words "distant particles can be correlated in ways that are impossible for classical objects" and find out what lead to that discovery? Or what does "Bell inequality" really mean? If not, are there recommended methods of understanding articles better? Venkman: Ray, pretend for a moment that I don't know anything about metallurgy, enginee…

Can you recommend an entry level Physics/QM book?

You can also look at some Susskind talks. He is a very good explainer. They don't skim on the math, but it's followable for somebody with a high-school level of math, at least for the basic concepts like spin or bell inequality.

https://www.youtube.com/watch?v=pyX8kQ-JzHI&list=PLQrxduI9Pd...

Re: Physicists demonstrate new way to violate local causality

#24
post #5

To someone who doesn't actually know many of the terms here, it sounds like they didn't accomplish much. They defined a stronger form of locality called "bi-locality" and found a way to violate it. The structure of the argument is, "We stood up a strawman and knocked it down," which sounds pretty weak. Is bi-locality an inherently interesting property? Does all classical computation follow it? I don't know enough to…

Your take makes it sound like "we had this awesome idea! but we tested it and we were wrong." I have no idea if you're correct, but that is indeed how science should work.

Nah, locality is expected to be violated. Bell test experiments have proven this for like forever, and rather recently a very accurate test with very few loopholes was conducted too.

They used a new kind of locality and proved it was broken too. Interesting, but not groundbreaking.

Re: Physicists demonstrate new way to violate local causality

#25

Earlier quoted context omitted.

Yes it's likely that I'm over-thinking this... It does not feel good enough since it would be ~opening new tabs and~ make me go through a lot more effort than necessary, and it feels like I would be overwhelmed and give up eventually. If there is something that would make "understanding articles as easy as possible" then that would be amazing. I'll probably end up developing this myself... Edit: was incorrect about o…

I was thinking a Chrome extension to automate this process would be a great way to turn "inaccessible science gibberish" into "Eli5" for a mass of people (I'd like to read that but I'm not willing to do any work other than install a Chrome xtension)

Not sure if that would really work. Understanding science, math, and engineering using analogies leads to misconceptions when one tries to apply them. The math is true understanding. If you understand the equation, then you not only understand the subject, but often what would happen if you tweaked the inputs...etc. Although it would be nice if Wikipedia had an ELI5 section on its physics articles to go through first, so I agree with you there.

Re: Physicists demonstrate new way to violate local causality

#26
post #14

To someone who doesn't actually know many of the terms here, it sounds like they didn't accomplish much. They defined a stronger form of locality called "bi-locality" and found a way to violate it. The structure of the argument is, "We stood up a strawman and knocked it down," which sounds pretty weak. Is bi-locality an inherently interesting property? Does all classical computation follow it? I don't know enough to…

> The structure of the argument is, "We stood up a strawman and knocked it down," which sounds pretty weak. Weaker than "I don't understand what the paper says, only read a high level layman summary, not sure even what what the experiment was for, but I'm gonna piss on it anyway"? Even assuming what you already describe, the ability to show bi-locality as a new lower bound above which locality constraints apply, is v…

It's amazing how so many people on the internet feel so confident in their own intellectual abilities that they can read something that they don't understand and dismiss it as if it's non-important.

Re: Physicists demonstrate new way to violate local causality

#27
post #23

Earlier quoted context omitted.

Can you recommend an entry level Physics/QM book?

You can also look at some Susskind talks. He is a very good explainer. They don't skim on the math, but it's followable for somebody with a high-school level of math, at least for the basic concepts like spin or bell inequality. https://www.youtube.com/watch?v=pyX8kQ-JzHI&list=PLQrxduI9Pd...

My first thought: iTunesU, Youtube, etc... there HAS to be tons of videos on "entry level" stuff like this...

Yale Entry Level Physics Class: https://itunes.apple.com/us/itunes-u/physics-video/id3416518...

https://www.youtube.com/results?search_query=Yale+physics

MIT Quantum Physics: https://itunes.apple.com/us/itunes-u/quantum-physics-i/id887...

https://www.youtube.com/results?search_query=mit+quantum+mec...

quick google searches should yield more classes easily enough.

Re: Physicists demonstrate new way to violate local causality

#29
post #14

Earlier quoted context omitted.

> The structure of the argument is, "We stood up a strawman and knocked it down," which sounds pretty weak. Weaker than "I don't understand what the paper says, only read a high level layman summary, not sure even what what the experiment was for, but I'm gonna piss on it anyway"? Even assuming what you already describe, the ability to show bi-locality as a new lower bound above which locality constraints apply, is v…

It's amazing how so many people on the internet feel so confident in their own intellectual abilities that they can read something that they don't understand and dismiss it as if it's non-important.

[deleted]

Re: Physicists demonstrate new way to violate local causality

#30
post #10

If anyone wants to learn more about Bell's inequality, the simplest (real, no bullshit) explanation I've ever seen is by David Griffiths. You can follow it if you know the basics of calculus: http://www.physics.umd.edu/courses/Phys270/Jenkins/Griffiths...

it's funny i read this years ago (at the end of second semester qm) and it never clicked. guess i've gotten smarter since then. thanks.
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