On a Frankl-Rödl theorem and its geometric corollaries

Abstract There are two main results in this paper. First, for any d ∈ N , we find an explicit c d > 1 such that χ d ( R n ) ≥ ( c d + o ( 1 ) ) n , where χ d ( R n ) is the minimum number of colors needed to color all points in R n so that there is no monochromatic set of vertices of a d-dimensional regular simplex. Second, for any k ≥ 3 we find an explicit ξ k > 1 such that for any n ∈ N , there exists a distance graph in R n with girth at least k and the chromatic number at least ( ξ k + o ( 1 ) ) n .