definition of the MST. We can formulate an equivalent characterization using
an ordering of edges instead.
-\defnn{Heavy and light edges}
+\defnn{Heavy and light edges}\thmid{heavy}%
Let~$T$ be a~spanning tree. Then:
\itemize\ibull
\:For vertices $x$ and $y$, let $T[x,y]$ denote the (unique) path in~$T$ joining $x$ and~$y$.