Drawing a Feynman Diagram: Lagrangian Basics

Thread starter daymio
Start date Feb 21, 2014
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Diagrams Feynman Feynman diagram Feynman diagrams

In summary, a Feynman diagram is a graphical representation of a mathematical expression that describes the probability amplitude of particle interactions. To draw one, you need to understand the rules and concepts of Feynman diagrams, and there are software programs available to assist. The Lagrangian is a crucial concept in Feynman diagrams as it is used to calculate the probability of particle interactions. These diagrams are essential in particle physics as they allow us to visualize and verify theories, but they are not applicable in every situation.

Feb 21, 2014

daymio

I need help :(
How can I draw a Feynman Diagram, starting with a Lagrangian?

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Feb 21, 2014

dauto

1st Step: Read through any good introductory Quantum Field Theory Book.
2nd Step: There is no second step

Feb 22, 2014

ChrisVer

Gold Member

depends on the fields participating in your lagrangian...and the feynman diagram rules

1. What does a Feynman diagram represent?

A Feynman diagram is a graphical representation of a mathematical expression called a Feynman integral, which describes the probability amplitude of a particle interaction. It shows the possible paths of particles, their interactions, and their final states.

2. How do I draw a Feynman diagram?

To draw a Feynman diagram, you will need to understand the basic rules of Feynman diagram construction, such as the use of lines to represent particles and vertices to represent interactions. You will also need to have a basic understanding of the relevant physical concepts, such as the conservation of energy and momentum. There are also various software programs available that can help you draw Feynman diagrams.

3. What is the Lagrangian in Feynman diagrams?

The Lagrangian is a mathematical concept used in quantum field theory to describe the dynamics of particles. It is a function that describes the interaction between particles and fields and is used to calculate the probability amplitude of particle interactions in Feynman diagrams.

4. What is the importance of Feynman diagrams in particle physics?

Feynman diagrams are an essential tool in particle physics as they allow us to visualize and calculate the probability of particle interactions. They also provide a way to test and verify the predictions of quantum field theory and are crucial in the development of new theories and models in particle physics.

5. Can Feynman diagrams be used for all particle interactions?

Feynman diagrams can be used to represent and calculate the probability of all known particle interactions, including electromagnetic, weak, and strong interactions. However, they are not applicable in every situation, such as in the case of interactions involving gravity, as it is not yet fully incorporated into quantum field theory.