2 papers
math.SP2025
Eigenvalues of Maximal Abelian Covers
Wenbo Li, Michael Magee, Mostafa Sabri +1
We fully characterize the eigenvalues (flat bands) of the maximal abelian cover of a finite multi-graph in terms of the combinatorics of the base graph. This solves a problem of Hi…
math.CO2025
A note on Puder's generalised co-growth formula for trees
Wenbo Li, Joe Thomas
In this note, we prove a conjecture of Puder on an extension of the co-growth formula to any non-negative function defined on a bi-regular tree. A key component of our proof is the…