Parameterized Complexity of Elimination Distance to First-Order Logic Properties

The elimination distance to some target graph propertyPis a general graph modification parameter introduced by Bulian and Dawar. We initiate the study of elimination distances to graph properties expressible in first-order logic. We delimit the problem's fixed-parameter tractability by identifying sufficient and necessary conditions on the structure of prefixes of first-order logic formulas. Our main result is the following meta-theorem: For every graph propertyPexpressible by a first order-logic formula φ ∈ Σ3, that is, of the form φ = ∃x1∃x2⋯∃xr∀y1∀y2⋯∀ys∃z1∃z2⋯∃ztψ, where ψ is a quantifier-free first-order formula, checking whether the elimination distance of a graph toPdoes not exceed k, is fixed-parameter tractable parameterized by k. Properties of graphs expressible by formulas from Σ3 include being of bounded degree, excluding a forbidden subgraph, or containing a bounded dominating set. We complement this theorem by showing that such a general statement does not hold for formulas with even slightly more expressive prefix structure: There are formulas φ ∈ Π3, for which computing elimination distance is W[2]-hard.