activity
20132026
most citedMicroarcsecond VLBI pulsar astrometry with PSR II. parallax distances for 57 pulsars

151 citations · 163 across the 9 of their papers we have counts for

collaborators

12 papers

math.RA2026

Dual Ploščica spaces of ortholattices

Andrew Craig, Miroslav Haviar

We describe digraphs with topology which give dual representations of ortholattices. This is done via so-called dual Ploščica spaces of lattices. First, we improve the definition o…

math.RA2025

Dual spaces of lattices and semidistributive lattices

Andrew Craig, Miroslav Haviar, José São João

Birkhoff's 1937 dual representation of finite distributive lattices via finite posets was in 1970 extended to a dual representation of arbitrary distributive lattices via compact t…

math.RA2023

Dual digraphs of finite meet-distributive and modular lattices

Andrew Craig, Miroslav Haviar, Klarise Marais

We describe the digraphs that are dual representations of finite lattices satisfying conditions related to meet-distributivity and modularity. This is done using the dual digraph r…

math.LO2020

Expanding Belnap 2: the dual category in depth

Andrew Craig, Brian A. Davey, Miroslav Haviar

Bilattices, which provide an algebraic tool for simultaneously modelling knowledge and truth, were introduced by N.D. Belnap in a 1977 paper entitled 'How a computer should think'.…

math.LO2020

Canonical extensions of lattices are more than perfect

Andrew P. K. Craig, Maria J. Gouveia, Miroslav Haviar

In \cite{CGH15} we introduced TiRS graphs and TiRS frames to create a new natural setting for duals of canonical extensions of lattices. In this continuation of \cite{CGH15} we ans…

math.LO2019

Modelling competing theories

Willem Conradie, Andrew Craig, Alessandra Palmigiano +1

We introduce a complete many-valued semantics for two normal lattice-based modal logics. This semantics is based on reflexive many-valued graphs. We discuss an interpretation and p…

math.LO2019

Modelling informational entropy

Willem Conradie, Andrew Craig, Alessandra Palmigiano +1

By 'informational entropy', we understand an inherent boundary to knowability, due e.g. to perceptual, theoretical, evidential or linguistic limits. In this paper, we discuss a log…

astro-ph.IM2018★ 151 cited

Microarcsecond VLBI pulsar astrometry with PSR II. parallax distances for 57 pulsars

A. T. Deller, W. M. Goss, W. F. Brisken +8

We present the results of PSR, a large astrometric project targeting radio pulsars using the Very Long Baseline Array (VLBA). From our astrometric database of 60 pulsars, we hav…

math.LO2016★ 12 cited

Constructive canonicity for lattice-based fixed point logics

Willem Conradie, Andrew Craig, Alessandra Palmigiano +1

We prove the algorithmic canonicity of two classes of -inequalities in a constructive meta-theory of normal lattice expansions. This result simultaneously generalizes Conradie a…

math.LO2014

Canonicity results for mu-calculi: an algorithmic approach

Willem Conradie, Andrew Craig

We investigate the canonicity of inequalities of the intuitionistic mu-calculus. The notion of canonicity in the presence of fixed point operators is not entirely straightforward.…

math.RA2013

Product representation for default bilattices: an application of natural duality theory

L. M. Cabrer, A. P. K. Craig, H. A. Priestley

Bilattices (that is, sets with two lattice structures) provide an algebraic tool to model simultaneously the validity of, and knowledge about, sentences in an appropriate language.…

math.RA2013

A fresh perspective on canonical extensions for bounded lattices

A. P. K. Craig, M. Haviar, H. A. Priestley

This paper presents a novel treatment of the canonical extension of a bounded lattice, in the spirit of thetheory of natural dualities. At the level of objects, this can be achieve…