deletions | additions       diff --git a/Payam.tex b/Payam.tex  index beb01f6..b90686e 100644  --- a/Payam.tex  +++ b/Payam.tex 
...
\begin{enumerate}  \item What happens if an interior piece approaches the pore?  \item In \cite{http://adsabs.harvard.edu/abs/2013PhRvE..87d2723R}, it is claimed that motion will be a superposition of longitudinal and transverse. Is this true -- won't one of them be unstable (in the case where work done in dragging is less than $T$, say)?  \end{enumerate}