Lecture 2 Flashcards
What is the value of the fine structure constant alpha?
1/137
What is alpha for the strong force?
About 1
What is alpha for the strong force?
About 1
What is alpha for the W and Z Weak force?
About 1/40
In a Feynman Diagram, which side (L or R) is the start?
Left
What do the arrows in a FD represent?
The Anti-particles have a -ve ‘time’ direction
In all inertial frames, what is constant?
C
What is Beta?
Beta = v/c
What are four vectors
Four component objects (like x = (ct,x,y,z)) which transform using Lorentz transformations
Contravariant four vectors have upper or lower index notation?
Upper
Covariant four vectors have upper or lower notation?
Lower
What is the relationship between a covariant and contravariant four vector?
contravariant = metric tensor * covariant
