Simplification of Dirac Notation

1. Oct 8, 2012

JordanGo

How would you simplify this expression:

<a|<b|a>|a>

where ψ = |a>|b> and I'm finding ψ*ψ.

2. Oct 9, 2012

dextercioby

Your notation is incomplete, thus misleading. Are you speaking of tensor products ?