This chapter is from the book
This chapter is from the book
This chapter is from the book
6.5 Feynman Diagram
For those readers who are a bit exhausted from all the mathematics presented in this chapter, there is help for you. Richard Feynman created the Feynman diagrams to provide a pictorial representation of the mathematical expressions used to describe the behavior of subatomic particles. This is a much easier way to at least capture the essence of what is occurring. Let us first look at the basic diagram symbols used and then see how they work together (see Table 6.1).
TABLE 6.1 Feynman Diagram Symbols
Description |
Symbol |
|---|---|
A fermion (i.e., electron, positron, quark, etc.) is drawn as a straight line with an arrow pointing to the direction of the spin. |
|
An antifermion is drawn as a straight line with an arrow pointing to the direction of the spin, with the primary difference being the line over the f. |
|
A photon is drawn as a wavy line. |
|
Therefore, if you wish to draw two electrons with opposite spin, colliding and producing a photon, you can use Feynman diagrams without any math, as demonstrated in Figure 6.2.
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FIGURE 6-2 Feynman diagram of electrons colliding
This is just a very brief introduction to Feynman diagrams, but you will find these useful as you learn more about quantum interactions.