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Feynman Diagram Question

Feynman diagrams are pretty hard to understand since time is on the y-axis, but what stumps me is why the diagram for electron-electron repulsion is the same as the one for proton-electron attraction? In both examples the two particles comes together then move apart. In electron-electron repulsion it is clear that this is due to the exchange of the virtual photon because like charges repel. But what about for the proton and electron?
Space isn't represented in a Feynman diagram. Its simply drew that way as its easier and less clutterful than respecting the motion afterwards.
Reply 2
Original post by JakeRStudent
Space isn't represented in a Feynman diagram. Its simply drew that way as its easier and less clutterful than respecting the motion afterwards.


So the Feynman diagram essentially just shows exchange particles and any new particles made?
Original post by Hughcifer
So the Feynman diagram essentially just shows exchange particles and any new particles made?
exactly.
Reply 4
Original post by JakeRStudent
exactly.


Damn it seems kinda dumb then. Thanks for your help!
Original post by Hughcifer
Damn it seems kinda dumb then. Thanks for your help!


At A-Level, they're very basic and don't say much. However, for the purpose for which Feynman first created them, they encode an incredible amount of otherwise awkward mathematics into one (often simple) diagram equipped with a set of rules to analyse them once you add other physical parameters like momentum, spin etc.

In short, they are an indispensable tool for understanding particle physics properly and really rather clever. Whilst they are undersold at A-Level (for obvious reasons) and I understand your underwhelmed reaction, this is a good example of how calling things dumb based on what you see at A-Level is unwise.
Original post by Hughcifer
Damn it seems kinda dumb then. Thanks for your help!


I mean if you think about it it's dumb to include a spatial dimension in a pictorial representation designed to simplify problems. These diagrams become a necessity at higher than a level, and are more so just a memory thing for you currently. You've got to understand that these things are used not because we needed some material to test students on but because they simplify problems immensely and allow us to visualise really REALLY complicated processes.

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