The Lovász conjecture holds for moderately dense Cayley graphs

We show that there is an absolute constant $c>0$ such that every large connected $n$-vertex Cayley graph with degree $d\ge n^{1-c}$ has a Hamilton cycle. This makes progress towards the Lovász conjecture and improves upon the previous best result of this form due to Christofides, Hladký, and Máthé from 2014 concerning graphs with $d\ge \epsilon n$. Our proof avoids the use of Szemerédi’s regularity lemma and relies instead on an efficient arithmetic regularity lemma specialised to Cayley graphs.