Lattice Embeddings in Percolation

Does there exist a Lipschitz injection of Z into the open set of a site percolation process on Z, if the percolation parameter p is sufficiently close to 1? We prove a negative answer when d = D, and also when d ≥ 2 if the Lipschitz constant M is required to be 1. Earlier work of Dirr, Dondl, Grimmett, Holroyd, and Scheutzow yields a positive answer for d < D and M = 2. As a result, the above question is answered for all d, D and M . Our proof in the case d = D uses Tucker’s Lemma from topological combinatorics, together with the aforementioned result for d < D. One application is an affirmative answer to a question of Peled concerning embeddings of random words in two and more dimensions.