deletions | additions       diff --git a/magnetoresistance.tex b/magnetoresistance.tex  index ad13e65..fc34707 100644  --- a/magnetoresistance.tex  +++ b/magnetoresistance.tex 
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\end{equation}  where  \begin{equation}  \sigma_0 = \frac{n q^2 \tau}P{m^*} \tau}{m^*}  \end{equation}  is the electrical conductivity in the absence of a magnetic field and  \begin{equation}