2 papers
math.SP2021
On the density of eigenvalues on periodic graphs
Cosmas Kravaris
Suppose that is a graph with vertices , edges , a free group action on the vertices with finitely many orbits, and a linear operat…
math.GR2020
On the growth of the wallpaper groups
Rostislav Grigorchuk, Cosmas Kravaris
We develop further Cannon's method of cone types for finding the growth function of a group, which can also be used to find the coordination sequences of certain infinite graphs. W…