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Quarks Know Their Left From Their Right

news.sciencemag.org

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Re: Quarks Know Their Left From Their Right

#2
Awesome result. I think it's vitally important to acknowledge achievements that happen in parallel with research at the LHC because otherwise we're going to miss a lot of very neat results. I don't know enough about particle physics to be able to comment on the techniques involved unfortunately, but I love reading about the progress that's being made.

For someone that Wikipedia's a lot of this stuff, does someone know if this type of spin asymmetry is in any sense related to CP violation? [1] As soon as I read the article I thought of CP violation and I'm assuming this is basically the "P" violation.

Finally, reading this article actually triggered a totally different question:

"Using the electron accelerator at Thomas Jefferson National Accelerator Facility in Newport News, Virginia, the researchers shined 170 billion electrons on a target of liquid deuterium over 2 months in 2009."

Shined or shone? Turns out to be quite the discussion topic (e.g., [2][3][4])!

[1] http://en.wikipedia.org/wiki/CP_violation

[2] http://public.wsu.edu/~brians/errors/shined.html

[3] http://grammarist.com/usage/shined-shone/

[4] http://motivatedgrammar.wordpress.com/2010/10/18/has-the-sun...

Re: Quarks Know Their Left From Their Right

#3
For a science magazine, this article does a terrible job of talking about spin. Saying "spinning as it zips along—to the right like a football thrown by a right-handed quarterback or the left like a pigskin thrown by a lefty" is immensely confusing to anyone who actually wants to understand what's going on.

Re: Quarks Know Their Left From Their Right

#4
post #3

For a science magazine, this article does a terrible job of talking about spin. Saying "spinning as it zips along—to the right like a football thrown by a right-handed quarterback or the left like a pigskin thrown by a lefty" is immensely confusing to anyone who actually wants to understand what's going on.

I've seen this trend several places recently.

People are trying to dumb down science so it can be "understandable", often by using sport-analogies. It doesn't help that these dumbed down sport-analogies often feature American sports seldom found in other countries.

The net effect is that if I was in need of a explanation, I'm still confused and all of a sudden annoyed at footballers too.

Re: Quarks Know Their Left From Their Right

#5
post #4
post #3

For a science magazine, this article does a terrible job of talking about spin. Saying "spinning as it zips along—to the right like a football thrown by a right-handed quarterback or the left like a pigskin thrown by a lefty" is immensely confusing to anyone who actually wants to understand what's going on.

I've seen this trend several places recently. People are trying to dumb down science so it can be "understandable", often by using sport-analogies. It doesn't help that these dumbed down sport-analogies often feature American sports seldom found in other countries. The net effect is that if I was in need of a explanation, I'm still confused and all of a sudden annoyed at footballers too.

Spinning ball analogy is very common in school or basic uni.

I think it is spinning ball 100% of the time.

Re: Quarks Know Their Left From Their Right

#6
post #3

For a science magazine, this article does a terrible job of talking about spin. Saying "spinning as it zips along—to the right like a football thrown by a right-handed quarterback or the left like a pigskin thrown by a lefty" is immensely confusing to anyone who actually wants to understand what's going on.

The problem with science magazines is that if you dumb down paper enough for general public to "understand" it there is basically nothing left.

Article doesn't even try to describe what this $2 C_{2 u}  − C_{2 d}$ coupling is all about.

If you're trying to follow High Energy Physics, your best choice is to follow abstracts in ArXiV (which in turn requires _some_ knowledge and education :-(.

Re: Quarks Know Their Left From Their Right

#7
post #3

For a science magazine, this article does a terrible job of talking about spin. Saying "spinning as it zips along—to the right like a football thrown by a right-handed quarterback or the left like a pigskin thrown by a lefty" is immensely confusing to anyone who actually wants to understand what's going on.

Can someone explain what's wrong with the spinning ball analogy? From my understanding, it's a pretty good first approximation of the physical interpretation of particle spin.

Re: Quarks Know Their Left From Their Right

#8
post #3

For a science magazine, this article does a terrible job of talking about spin. Saying "spinning as it zips along—to the right like a football thrown by a right-handed quarterback or the left like a pigskin thrown by a lefty" is immensely confusing to anyone who actually wants to understand what's going on.

Which is why I have so much respect for Richard Feynman. His books, especially QED, are so well written that I could understand the most part while still being able to appreciate the complexities. I believe he has said something to the effect of "if I can not make a lay person understand complex phenomenon it only means I have not understood it fully yet.

Re: Quarks Know Their Left From Their Right

#9
post #3

For a science magazine, this article does a terrible job of talking about spin. Saying "spinning as it zips along—to the right like a football thrown by a right-handed quarterback or the left like a pigskin thrown by a lefty" is immensely confusing to anyone who actually wants to understand what's going on.

Can someone explain what's wrong with the spinning ball analogy? From my understanding, it's a pretty good first approximation of the physical interpretation of particle spin.

Elementary particles are dots for all intents and purposes. But dots can't spin. Spinning requires internal structure to notice spinning, but elementary particles don't have it.

Basically you don't need analogy at all.

Spin is inherent property of a particle like mass, charge, etc. It's quantum like charge. If lagrangian of interaction includes particle's spin, spin effects will be noticeable in scattering and everywhere.

Analogy is only needed to not mix spin with angular momentum.

Funny how in media spin is left and right, but in science spin is always "up" or "down". :-)

Re: Quarks Know Their Left From Their Right

#10

Earlier quoted context omitted.

Can someone explain what's wrong with the spinning ball analogy? From my understanding, it's a pretty good first approximation of the physical interpretation of particle spin.

Elementary particles are dots for all intents and purposes. But dots can't spin. Spinning requires internal structure to notice spinning, but elementary particles don't have it. Basically you don't need analogy at all. Spin is inherent property of a particle like mass, charge, etc. It's quantum like charge. If lagrangian of interaction includes particle's spin, spin effects will be noticeable in scattering and everyw…

Agreed, but you will also agree that you've gone well beyond the level of first approximation here, right?
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