Comments

• maximum allowable time-step is optimal:

  $$v_{0}\geq \max_{grid}\left(\sqrt{\frac{3(\lambda+2\mu)}{\rho}}\right) = \sqrt{3}c_{P}$$

  
  
  under an appropriate choice of impedances in the network.
• Required vector wave variables, so need to pay attention to implementation of vector junction (in finite arithmetic).

• Multidimensional circuit approach works as well, but time-step is sub-optimal.

• Free boundary is simple to implement, in a perfectly lossless manner.
• Need to perform a time-integration (somehow) in order to get displacements.