Please send me E-mail, dow@ubpheno.physics.buffalo.edu, no later than Monday, April 10, 2006, 2 pm, with your thoughts on:

1. Why is quantum mechanics not a sufficient physical framework to describe fundamental particles and their interactions ?
(hint: describe the main feature of the transition from quantum mechanics to a quantum field theory.)

2. What do we believe are the fundamental physical principles that shape the theory of fundamental particles and their interactions ?

3. What happens when we "gauge a theory" ?