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Feynman Diagrams

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Feynman diagrams are schematic representations of particle interactions. They are not pictures or sketches of the interactions, and they do not represent what might be seen in a cloud chamber or a photographic plate.

Feynman diagrams are presented with a time direction. Originally the time direction is positive upwards, but today many use a time dimension which is positive rightward. The other dimension is space. But because the diagrams are schematic, the dimensions are not scaled and the space dimension is no particular direction.

"Electron Repulsion Feynman Diagram"
A Feynman Diagram

A Feynman Diagram

The numbering is according to a chalk diagram by Feynman in the University of Auckland lectures (https://youtu.be/aVLTeeaQnXs?t=40m36s). Particle labels and fermion direction arrows have been add.

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Sources:

Recommended:

Categories: Standard Model Feynman Diagrams

This is a student's notebook. I am not responsible if you copy it for homework, and it turns out to be wrong.