Chladni figures of discrete square

Here are the Chladni figures (nodal curves) of all the eigenvectors of G=(L3 x L3) x K1, a discrete square graph with 113 vertices (the discrete square L3 x L3 has 25 vertices and 56 edges and 32 triangles adding up to 113 simplices. Click on a picture to see it larger. These pictures correspond to the classical Chladni figures on a plate one can observe when putting sand on a plate vibrating with an eigenfrequency: the sand particles rest only where the eigenfunction is zero and get thrown away at other points. See pictures like this example from MIT. The level surfaces fk = 0 for the eigenfunctions fk are in the Barycentric refinement G x K1. See the "The graph spectrum of barycentric refinements" or Sard theorem for graph for the math and mini blog, Same pictures for G3 of triangle, Same pictures for G3 of triangle, and of a polyhedron.