Moon Duchin, a professor of mathematics at Tufts University, uses metric geometry to help defend democracy against the threat posed by gerrymandering. But as she discusses with host Steven Strogatz, the problem of fair voting in a representative democracy can't simply be reduced to an objective function. This episode was produced by Dana Bialek. Read more at Quantamagazine.org. Production and original music by Story Mechanics. This episode was produced by Dana Bialek. Read more at Quantamagazine.org. Production and original music by Story Mechanics.