Solve Lagrangian Deduc Vertex Problem Easily

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SUMMARY

The discussion focuses on deducing the vertex from a Lagrangian in quantum field theory. Participants emphasize examining the interacting terms of the Lagrangian, specifically those that are not kinetic or mass terms. To derive the corresponding Feynman rule, one must add an "i" to the term and eliminate the fields. For vertices involving three or four vector bosons, the calculation becomes more complex, necessitating consideration of the various interaction configurations, as detailed in Peskin's textbook on page 507.

PREREQUISITES
  • Understanding of Lagrangian mechanics
  • Familiarity with Feynman diagrams and rules
  • Knowledge of quantum field theory
  • Access to Peskin's textbook on quantum field theory
NEXT STEPS
  • Study the interacting terms in Lagrangians
  • Learn how to derive Feynman rules from Lagrangian terms
  • Examine the complexities of interactions involving multiple vector bosons
  • Review Peskin's textbook, specifically page 507, for detailed examples
USEFUL FOR

Physicists, students of quantum field theory, and anyone interested in understanding particle interactions through Lagrangian mechanics.

ElianeUnifei
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I want deduc vertex of the lagrangian, but I not know how?
 
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If you mean, which particles interact you just have look at the interacting terms of the Lagrangian. In general just look at the ones that aren't kinetic or mass terms.

To calculate the associated Feynman rule just keep the term add an "i" and remove the fields. If you have a vertex with 3 or 4 vector bosons the Feynman rule is bit more complicated because you have to take into account the different ways in which they can interact. Check it out for example in Peskin pag 507.
 

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