Coherent State: What Does Re Mean?

[physgirl]

Coherent state... "Re"?

So we're talking about coherent state of harmonic oscillator... and for |psi(x,t)|^2, we came up with an equation... that has a term with "Re" in it. Does anyone know what I'm talking about or should I type up the whole equation? What does the "Re" mean?>?>

 

[marcusl]

The whole equation would be helpful but usually Re means "real part". Since you're taking the magnitude squared, you have psi times complex conjugate of psi and if psi is a sum of terms it can happen that you get the sum of two cross terms that are complex conjugates of each other.

 

[Poop-Loops]

Re[blah blah] usually means "take the real part" and Im[blah blah] means "take the imaginary part".

This tends to come up in classical mechanics a bit, too, since you don't really see imaginary solutions to equations of motion.