- #1
Niles
- 1,866
- 0
Homework Statement
Hi
I have a technical question regarding the following paper: http://arxiv.org/pdf/quant-ph/0602170v1.pdf
In it they derive an equation for [itex]\left\langle a \right\rangle[/itex] (equation #5) from the master equation (equation #2). My question is how they do this. Here is what I know
[tex]
\left\langle {\dot a} \right\rangle = \text{Tr}[a\dot\rho]
[/tex]
My problem comes when I have to evaluate this expression. The trace is to be taken over the system states, but what are these?
I would be very happy to get a push in the right direction.
Niles.