- 254

- 5

- a

^{+}|n>=D|n+1>

And because |n-1> is normalized, <n-1|n-1>=1: (<n|a

^{+})(a|n>)=C

^{2}

Thus, <n|a

^{+}a|n>=C

^{2}

Where a is the annihilation operator and a

^{+}is the creation operator

I don't understand this as isn't <n|a

^{+}=<n+1|D , thus <n|a

^{+}a|n> =<n+1|DC|n-1> instead?

This is from the quantum physics for dummies.