Combinatorial properties of bounded merge-width classes

Prove that every graph class of bounded merge-width is polynomially chi-bounded, has the strong Erdős–Hajnal property, and admits adjacency labelling schemes of size \(O(\log n)\).

Background

Bounded twin-width classes and structurally bounded-expansion classes share several combinatorial properties: polynomial chi-boundedness, the strong Erdős–Hajnal property, and logarithmic-size adjacency labelling schemes. Since both are examples of bounded merge-width, the paper conjectures that these properties extend to all bounded merge-width classes.

References

We conjecture that classes of bounded merge-width also enjoy all those properties.

Merge-width and First-Order Model Checking  (2502.18065 - Dreier et al., 25 Feb 2025) in Section “Discussion”, paragraph “Combinatorial properties”