Particle interactions

  2. Atomic, nuclear and particles
  3. Structure of matter
  4. Particle interactions
    5. 10'

Particle interactions can be represented by Feynman diagrams governed by simple rules:

  • One in, one out
  • Two straight, one wiggly

Key Concepts

Conservation rules

The following quantities must be conserved during particle interactions:

  • Baryon number
  • Lepton number
  • Strangness (but not in weak interactions)
  • Charge
  • (Mass-energy)

 

Exchange particles and forces

The forces that exist are all a result of the exchange of particles.

 

 

Essentials

Feynman diagrams

Look out for the rules described on the Structure of matter page.

First, notice the effect of rotating the lines.

 

Complex interactions

Now look for the effects of these subtle variations in the lines for a more complex interaction.

 

Test Yourself

Use quizzes to practise application of theory.


START QUIZ!
 

Exam-style Questions

Online tutorials to help you solve original problems

 
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