10 citations · 11 across the 5 of their papers we have counts for
5 papers
Finite model theory for pseudovarieties and universal algebra: preservation, definability and complexity
Lucy Ham, Marcel Jackson
We explore new interactions between finite model theory and classical streams of universal algebra and semigroup theory. A key result is an example of finite algebras whose variety…
Axiomatisability and hardness for universal Horn classes of hypergraphs
Lucy Ham, Marcel Jackson
We characterise finite axiomatisability and intractability of deciding membership for universal Horn classes generated by finite loop-free hypergraphs.
All or nothing: toward a promise problem dichotomy for constraint problems
Lucy Ham, Marcel Jackson
A finite constraint language is a finite set of relations over some finite domain . We show that intractability of the constraint satisfaction problem $\operatorna…
Gap theorems for robust satisfiability: Boolean CSPs and beyond
Lucy Ham
A computational problem exhibits a "gap property" when there is no tractable boundary between two disjoint sets of instances. We establish a Gap Trichotomy Theorem for a family of…
Relativised homomorphism preservation at the finite level
Lucy Ham
In this article, we investigate the status of the homomorphism preservation property amongst restricted classes of finite relational structures and algebraic structures. We show th…