We prove that several problems concerning congruences on algebras are complete for nondeterministic log-space. These problems are: determining the congruence on a given algebra gen...
In this paper we consider the complexity of several problems involving finite algebraic structures. Given finite algebras A and B, these problems ask the following. (1) Do A and B ...
We present algebraic conditions on constraint languages Γ that ensure the hardness of the constraint satisfaction problem CSP(Γ) for complexity classes L, NL, P, NP and ModpL. Th...
We describe some major recent progress in exact and symbolic linear algebra. These advances concern the improvement of complexity estimates for fundamental problems such as linear...
We obtain lower bounds in the algebraic computation tree model for deciding the separability of two disjoint point sets. In particular, we show (n log n) time lower bounds for sep...
Esther M. Arkin, Ferran Hurtado, Joseph S. B. Mitc...