why you can't explain qcd

"Angela Collier is my favourite YouTube science communicator" - Albert Einstein

The video really delivers on its promise, at the beginning of my shower I didn't understand QCD and at the end of my shower I still do not understand QCD.

"You can't explain it to a six year old because it takes 4 years of undergrad and 4 years of grad school-" Ok, so they must be at LEAST 8 years old. Got it.

"Those are cartoons. They're not math." Angela shoving a category theorist into his locker.

“Albert Einstein catching strays from Dr. Collier is one of my favorite things about this channel.” - Mark Twain

Watching at 2x speed so I can not understand QCD in less than 20 mins

I would like to propose that "Quantum Gastrodynamics" is a way better term for weak force flavor interactions.

I'm really glad that this professional science communicator was able to ensure I understood that I do not understand QCD.

> sign up for a qcd lecture > Ask the professor if it's really about qcd or if it's just qed > They don't understand > Prepare a half hour YouTube video about the difference between qcd and qed > They laugh "it's a qcd lecture" > Attend > It's all qed

"Doesn't that suck for Einstein?...People just make stuff up and they say Einstein said it." -Albert Einstein

“W boson?? More like L bozo”— my attempt at a joke

My mental model of the relative complexity: QED: watching 2 or 3 billiard balls run into each other on a nice smooth pool table. QCD: watching a writhing ball of spaghetti the size of the solar system and oh yeah, the spaghetti is moving at nearly the speed of light and is made up of super-powerful magnets.

“ I’m saying words but math math math.” I think I need a T-shirt that says this.

At CalTech in 1970 (and probably in his books later) Feynman described trying to tell his father, an intelligent layperson, about what he did. I remember Feynman telling how, when his father asked “when the neutron becomes an electron and a proton, was the electron always there ‘inside’ the neutron?” “And I couldn’t explain it to him.”

The more I listen to Dr Collier, the more I realize I don't know shit about fuck but also the more I enjoy realizing this about myself. Dr Collier is a superhero. Her power is knowledge. Her secret weapon is an anti-crackpot-Dunning-Krueger-syndrome-theorists mischievous smile. Thank you so much.

I don't know if you have ever tried to explain something to a 6 year old, but they will ask you why about a thousand times while you are explaining something. To me, this is the root of the quote. It is not about being able to get the 6 year old to understand or have them be able to explain in the future. It is about being able to answer all of their why questions. If you can accurately answer all of their questions then you fully understand the subject.

When I was 6 years old I would get into trouble for mixing the colors of my Play-Doh. Imagine my horror if someone had tried to teach me that it was ok for quarks.

My explanation of why QCD is hard (for physicists to do, which is kind of a different matter from why it's difficult to explain) is to show Feynman diagrams and explain roughly what they mean, then say: "you can always draw more and more complicated diagrams. With QED, these diagrams get less and less important, so you can often get away with ignoring them past a point, and get a pretty good answer by only computing the simple ones. With QCD, the complicated diagrams get more important, so you can't get away with that kind of trick."

You definitely can explain QCD to a six year old, it's just the explanation takes usually about two decades.

Einstein once said: "I have predicted many things in my life. My theory can predict Mercury's precession. My theory predicts black holes. But the prediction I am most proud off is that 12 year olds will incorrectly attribute quotes to me on the internet."