How To Read Feynman Diagrams

A Feynman diagram is a picture of what happens when particles interact with each other. I in this video I explain what you need to know to understand Feynman diagrams, show you what all the particles in the standard model are, as well as which lines we use to represent them. And the general rules the fundamental particles follow as well as which particles take part in interactions via the fundamental forces.

#particle #physics #DomainOfScience

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Romantic Music: Touching Moment by Wayne Jones
Art, animation, editing by Dominic Walliman

[domainofscience]

Hey this is a re-uploaded version of this video as the first one contained a couple of errors which I wanted to fix. Hopefully this is basically free of errors now, but let me know if you spot anything. Also what do you think of the funny bits? Yay or nooo?

[bengoody]

Good afternoon sir! When you started off by saying you`re going to teach me how to read Feynman diagrams i paused your video, chuckled and said to myself .. "You can try" ... BUT i have to confess you made me understand. When i got towards the end and you proposed the specific question "what force is mediating this interaction" .. Gluon - Strong Force!

[Schmuckimaster]

The last diagram looks like a strong proton-nucleon interaction. So basically what makes nuclei stick together. The down and up quark exchange can be viewd as an exchange of a virtual pion. So its more a "remnant" strong interaction, since its not directly transferred via gluons. Great video!
Edit: typo

[gfconstantino]

7:37 - The last Feynman Diagram depicts an Strong nuclear interaction between an Neutron (comprised of Up-Down-Down Quarks) and an Proton (comprised of Up-Down-Up quarks). In this quantum process, the initial Neutron (bottom-left of the Time-Space (TS) graph; T is Y-axis and Space is X-axis) is transformed into an Proton (upper-left of the TS graph) and the initial Proton (bottom-right of the TS graph) is transformed into an Neutron (upper-right of the TS graph). The gluons are always made of pairs (Color-G and anticolor-B or -Red, or Color-R and anticolor-G or -Color- B...). So the gluons (Strong force gauge bósons) change the individual color-charge of the quarks inside an NUCLEON - PROTON or NEUTRON, (in an dynamic; never-ending manner); BUT is by the process of creation and annihilation of PIONS (in this case, symbol-Pi -1; made always by a pair of quark anti-quark (both FERMIONS) and depicted as crossed solid lines), drawn in the MIDDLE of the TS graph as crossed lines that makes possible for different NUCLEONS to BE HELD TOGETHER by the STRONG NUCLEAR INTERACTIONS...(in this case by the STRONG RESIDUAL NUCLEAR INTERACTION)!

GREAT VíDEO DoS!
For more details:

[EventHorizon]

8:00 probably the nicest "zoomed in" depiction of the residual strong force I've seen.

[Fizikakaalda]

Dear, Dominic
Thank you for this amazing topic
It really drives me towards Quantum Physics. As a high school student, I am very grateful to you Dominic

[RCSmiths]

Thank you for working on the corrections. Really great video!

[zyansheep]

"That's all photons, _they're wiggly_ "

[camellkachour]

I feel impressed by these incredible guys who do a lot of efforts to try to explain us deep ideas of Physics. Big Thank You Very Much !

[abhishalsharma]

Explained so interestingly and simply only within 9 minutes.
That's really appreciating

[xXYourShadowDaniXx]

Love the art, animations, and inclusion of every particle in the standard model, very cool

[saintburnsy]

Have you uploaded the second part to this? Can't wait to learn more! You're doing great work m8

[robertschlesinger]

Excellent video. Very interesting, informative and worthwhile video. A must see for everyone interested in science, and most everyone not particularly interested in science. Many thanks.

[gravimagswnforce]

Great! very well explained! thank you so much for the knowledge!👍

[mdmem]

Wow, so easy to understand ^^ great work

[manavnaik]

Lw becoming one of my fav science channels for your realistic approaches.

[Ciencillamente]

2:02 This is just the best explanation of the standard model ever!

[hamadaag]

at 7:39 the reaction is mediated by the strong force (cus gluons) and it describes an up quark (bottom right) spontaneously turning into: an anti-up quark + down quark, turning into a down quark. At the same exact time a down quark (bottom left) interacts with the anti-up quark + down quark, turning into an up quark.

This can be thought of as: u (bottom right) --> anti-u + d + d (top right) and d (bottom left)+ d + anti-u --> u (top left) happening at the same time, each on its own breaks conservation laws but when put together: u + d --> u + d it obeys those laws, and its almost as if the up and down quarks "switched places"

You can also rewrite the equations, substituting (d + anti-up) with (negative pion): u (from bottom right) --> negative pion + d (top right) and d (from bottom left) + negative pion --> u (top right) both happening simultaneously. If you, dear fellow commenter, want to derive this yourself, you can write the feynman diagrams starting from the bottom right up quark ending with the top right down quark, and the same starting from the bottom left down quark ending with the top left up quark. Then you can combine the two feynman diagrams and you'll see the common pion arise between the two.

[Yekemcar]

Thank you sooo much for this video, and to make me update with new version of Physics. Since I finished my school !

[FCPSjdmahoney]

Using this today to start my lesson on particle physics with my higher level IB physics students. Thank you so much! Even my husband enjoyed it!