Recognition of probe H-free graphs and identification of probes

Develop polynomial-time recognition algorithms for probe H-free graphs and determine the distinction between probes and non-probes for general graphs H.

Background

In the probe graph model, the input graph is accompanied by a partition into probes and non-probes, with only edges involving probes known explicitly. Although recognition is possible for some forbidden graphs such as P_4, the paper states that recognition and identification of the probe/non-probe partition remain unresolved for most graphs H. Consequently, the paper generally studies partitioned probe H-free graphs, where the partition is supplied as part of the input.

References

However, for most graphs~$H$, the recognition of probe $H$-free graphs and the distinction between probes and non-probes are open problems.

Colouring Probe $H$-Free Graphs  (2505.20784 - Paulusma et al., 27 May 2025) in Section 1, Introduction, subparagraph “Our Focus”