On the existence of solutions for Frenkel-Kontorova models on quasi-crystals.

We focus on the recent development of the investigation on the equilibria of the Frenkel-Kontorova models subjected to potentials generated by quasi-crystals. We present a specific one-dimensional model with an explicit equivariant potential driven by the Fibonacci quasi-crystal. For a given positive number {\theta} , we show that there are multiple equilibria with rotation number {\theta} , e.g., a minimal configuration and a non-minimal equilibrium configuration. Some numerical explorations of of finding these equilibira are provided.