Question about Feynman diagram showing annihilation

AI Thread Summary
The discussion centers on a Feynman diagram depicting annihilation, specifically questioning the significance of a middle line with an arrow pointing right. It is clarified that this line represents an electron, not a W boson, as a W-line would violate Lorentz and electroweak gauge symmetries. The possibility of removing the horizontal line to simplify the diagram is dismissed, emphasizing that it is essential for maintaining conservation of energy and momentum. The conversation highlights the importance of accurately interpreting Feynman diagrams in particle physics. Understanding these diagrams is crucial for grasping fundamental interactions.
songoku
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Homework Statement
Please see below
Relevant Equations
Feynman Diagram
1713001049977.png


This is Feynman diagram of annihilation I get from wikipedia
https://en.wikipedia.org/wiki/Annihilation

I don't understand what the middle line with arrow to the right is. If I consider the left vertex and conservation of charge, it means the horizontal line with arrow to the right should carry negative charge. So it is W-?

Thanks
 
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It is an electron line.

A W-line would violate both Lorentz symmetry and electroweak gauge symmetry.
 
Orodruin said:
It is an electron line.

A W-line would violate both Lorentz symmetry and electroweak gauge symmetry.
Can the horizontal line be removed so the diagram only shows two lines (one for electron and one for positron) and two photons?

Thanks
 
songoku said:
Can the horizontal line be removed so the diagram only shows two lines (one for electron and one for positron) and two photons?

Thanks
No, absolutely not.
 
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Orodruin said:
No, absolutely not.
Is the reason related to post #2? And maybe also related to conservation of energy and momentum?

Thanks
 

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