deletions | additions       diff --git a/Introduction.tex b/Introduction.tex  index bd06799..15f3654 100644  --- a/Introduction.tex  +++ b/Introduction.tex 
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P=i\sqrt{\frac{\hbar \omega m}{2}}(a^+ -a) \\  H=\frac{P^2}{2m} + \frac{m\omega^2X^2}{2}  \end{equation}  Using the fact $rr^+=s^+s$ Can end up writing \begin{equation}  H=\frac{\hbar \omega}{2}(srr^+s^++r^+s^+sr) \\  H=\frac{\hbar \omega}{2}(ss^+ss^++r^+rr^+r)  \end{equation}  \\  \\  \\