  We show that minimal-surface non-Euclidean elastic plates share the same
low-energy effective theory as Haldane's dimerized quantum spin chain. As a
result, such elastic plates support fractional excitations, which take the form
of charge-$1/2$ solitons between degenerate states of the plates, in strong
analogy to their quantum counterpart. These fractional solitons exhibit
properties similar to fractional excitations in quantum fractional topological
states, including deconfinement and braiding, as well as unique new features
such as holographic properties and diode-like nonlinear response, demonstrating
great potentials for applications as mechanical metamaterials.
