I am trying to get something like this:
It resembles the political compass. There are 4 axis, all of them always positive, and two curves are shown. One of them obeys the equation:
$d(M)=M^{0.2}$
and for the other:
$d(M)=M^{-0.2}$.
There are also two horizontal lines for $d=1$. And the origin of the graph is at $(1,0)$. The two curves are flipped like the picture. It would look nicer if the left and right sides of the graph had different background colors, like red and blue. How can I do that?