deletions | additions       diff --git a/2QEnergies.tex b/2QEnergies.tex  index 8b8c591..a2d7ecc 100644  --- a/2QEnergies.tex  +++ b/2QEnergies.tex 
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Calculate now the matrix's elements in order to find later the eigene energies of the system. To do that it is usefull to calculate the matrix's elements  \begin{equation}  \begin{split}  &=\Epsilon_N\delta_{sn}\delta_{tm}\\  &=\Epsilon_1(1-\delta_{sn})\delta_{tm}+\Epsilon_2\delta_{sn}(1-\delta_{tm}) &=\epsilon_N\delta_{sn}\delta_{tm}\\  &=\epsilon_1(1-\delta_{sn})\delta_{tm}+\epsilon_2\delta_{sn}(1-\delta_{tm})  \end{split}  \end{equation}