activity
20242026
collaborators

6 papers

math.LO2026

Continuous graph homomorphisms of higher dimensional abelian group actions

Ruijun Wang

For every fixed integer , we prove that the finite graphs receiving a continuous homomorphism from the standard Schreier graph form a -complete…

math.LO2026

Finite Borel asymptotic dimension of bounded-to-one commutative monoid actions

Ruijun Wang

We prove that every bounded-to-one action of a finitely generated commutative monoid has finite asymptotic dimension, without a freeness assumption. If the group completion has tor…

math.LO2026

Borel graphs generated by finitely many bounded-to-1 commuting Borel functions and hyperfinite equivalence relations

Ruijun Wang

We show that a Borel graph generated by finitely many bounded-to-1 commuting functions is hyperfinite. This recovers a theorem in the forthcoming paper by Naryshkin, Shinko, Weilac…

math.LO2026

The continuous oriented chromatic number of directed Schreier graphs of -shift actions

Ruijun Wang

Let be the directed Schreier graph on the free part of the Bernoulli shift , with arcs in the two coordinate…

math.LO2025

Borel Kernels in Borel Directed Graphs

Ruijun Wang

We prove that there is a Borel quasi-kernel in any locally countable Borel directed graph with finite Borel chromatic number. We prove that the Borel chromatic number of a Borel di…

math.CO2024

Continuous Edge Chromatic Numbers of Abelian Group Actions

Su Gao, Ruijun Wang, Tianhao Wang

We prove that for any generating set of , the continuous edge chromatic number of the Schreier graph of the Bernoulli shift action is $…