2 citations · 2 across the 8 of their papers we have counts for
10 papers
Locally finite Schreier Varieties
Keith A. Kearnes, Andrew Moorhead, Agnes Szendrei
A variety is called a Schreier variety if every subalgebra of a -free algebra is a -free algebra. We use ideas from Tame Congruence Theory t…
Higher-dimensional generalized quasiorders
Andrew Moorhead, Reinhard Pöschel
It is well known that the polymorphism clone of a quasiorder is determined by its unary part, in the sense that any operation is a polymorphism if it satisfies the condition that a…
The class of congruence meet semidistributive varieties is not strong Maltsev
Andrew Moorhead
We present a proof that there is no single finite package of identities which characterizes the class of congruence meet semidistributive varieties.
Conservative Maltsev Constraint Satisfaction Problems
Manuel Bodirsky, Andrew Moorhead
One of the central open problems to classify the computational complexity of finite-domain constraint satisfaction problems within P is to prove better algorithmic results for CSPs…
Mal'cev Complexes
Andrew Moorhead
It is well known that an equivalence relation is invariant under the basic operations of an algebra if and only if it is invariant under the unary polynomials of the algebra. We sh…
Higher Kiss Terms
Andrew Moorhead
We show that the modular term condition higher commutator is equal to the modular hypercommutator. As a consequence, we arrive at a new proof that HC8 holds for modular varieties.…
Supernilpotent Taylor algebras are nilpotent
Andrew Moorhead
We develop the theory of the higher commutator for Taylor varieties. A new higher commutator operation called the hypercommutator is defined using a type of invariant relation call…
Supernilpotence Need Not Imply Nilpotence
Matthew Moore, Andrew Moorhead
Supernilpotence is a generalization of nilpotence using a recently developed theory of higher-arity commutators for universal algebras. Many important structural properties have be…
Some notes on the ternary modular commutator
Andrew Moorhead
We define a relation that describes the ternary commutator for congruence modular varieties. Properties of this relation are used to investigate the theory of the higher commutator…
Higher Commutator Theory for Congruence Modular Varieties
Andrew Moorhead
We develop the basic properties of the higher commutator for congruence modular varieties.