Hedlund-Metrics and the Stable Norm
  The real homology of a compact Riemannian manifold $M$ is naturally endowed with the stable norm. The stable norm on $H_1(M,\mathbb{R})$ arises from the Riemannian length functional by homogenization. It is difficult and interesting to decide which norms on the finite-dimensional vector space $H_1(M,\mathbb{R})$ are stable norms of a Riemannian metric on $M$. If the dimension of $M$ is at least three, I. Babenko and F. Balacheff proved in \cite{baba} that every polyhedral norm ball in $H_1(M,\mathbb{R})$, whose vertices are rational with respect to the lattice of integer classes in $H_1(M,\mathbb{R})$, is the stable norm ball of a Riemannian metric on $M$. This metric can even be chosen to be conformally equivalent to any given metric. The proof in \cite{baba} uses singular Riemannian metrics on polyhedra which are finally smoothed. Here we present an alternative construction of such metrics which remains in the geometric framework of smooth Riemannian metrics. 
Madeleine Jotz