deletions | additions       diff --git a/Intro.tex b/Intro.tex  index 0c2b52b..6539ab1 100644  --- a/Intro.tex  +++ b/Intro.tex 
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\[ P_3(t) = \left(\begin{array}{c}0 & 0 & 0 & F\\\end{array}\right) x(t)\]  such thatin operator form,  $F \cdot = \avg{\mu \cdot}$. \cdot}$, in operator form.  $x(t)$ is governed by the time evolution equation \[ \pd{x(t)}{t} = \left( \begin{array}{cccc}  0 & 0 & 0 & 0 \\ 
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0 & 0 & A & 0 \\  \end{array} \right) x(t) \]   where $x(0) = \left( \begin{array}{cccc}  \rho(0) \\  0 \\  0 \\  0 \\  \end{array} \right) $ and $A \cdot = \frac{-i}{\hbar}[H(t),\cdot]$ in operator form.