- #1
praharmitra
- 308
- 1
I am having some trouble understanding the paragraph after eq (3.93) in Peskin Schroeder (Page 55). The chapter is on the Dirac Field. These are the parts where I am not following:
1. If the ground state |0> is to be invariant under translations, we must have
|0> = e^{i \textbf{P.x}} |0>.
How?!
2. How does
<0| a^r_p {a^s_q}^\dagger e^{i P.x} |0>= e^{i(p-q).x} <0| e^{i P.x} a^r_p{a^s_q}^ \dagger |0>.
?!
Thanks :)
1. If the ground state |0> is to be invariant under translations, we must have
|0> = e^{i \textbf{P.x}} |0>.
How?!
2. How does
<0| a^r_p {a^s_q}^\dagger e^{i P.x} |0>= e^{i(p-q).x} <0| e^{i P.x} a^r_p{a^s_q}^ \dagger |0>.
?!
Thanks :)
