Use the Baker-Campbell-Hausdorff identities. They are your best friends for this. Two links, for example, http://planetmath.org/encyclopedia/BCHFormula.html , and http://www.mathematics.thetangentbundle.net/wiki/Linear_algebra/Baker-Campbell-Hausdorff_formula . Wikipedia has a page, http://en.wikipedia.org/wiki/Baker%E2%80%93Campbell%E2%80%93Hausdorff_formula , that has an example under the heading "Application in Quantum Mechanics" that is pretty much what you need.
Best, Peter.

Scalar product of coherent states 
I know that a PC can have multiple network adapters each of which with different network identifiers (IP,MAC etc.). 

My question is, can a certain PC have more than one active default gateway? And if so, how does the PC (or better say the OS) knows to what adapter use for any given packet?
