Question about Feynman diagram showing annihilation

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Homework Help Overview

The discussion revolves around the interpretation of a Feynman diagram depicting particle annihilation, specifically focusing on the representation of charge and particle lines within the diagram.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the meaning of the middle line in the diagram, questioning whether it represents a W- boson or an electron. There is also a discussion about the possibility of simplifying the diagram by removing certain lines.

Discussion Status

The conversation includes attempts to clarify the nature of the lines in the Feynman diagram, with some participants providing insights into the implications of removing lines and the associated conservation laws. There is no explicit consensus, but guidance has been offered regarding the nature of the lines.

Contextual Notes

Participants are considering conservation laws, including charge, energy, and momentum, in relation to the Feynman diagram. The original poster references external sources for context.

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.
 
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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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