Emma McDougall

Mathematics, Heriot-Watt

Tenure since 2014Emma 1

Low dimensional homotopy for inverse semigroups

Emma's research is concerned with different ways to describe algebraic structures that model symmetry.

The structures are groups and inverse semigroups, and they can be described concisely by presentations -- in effect, a short list of rules for carrying out computations. However, the same structure can be described by quite different sets of rules, and the question then arises of how we compare different presentations, and perhaps decide on the selection of an optimal one. The relevant properties of a particular presentation are encoded in its "Squier complex", which records the effects of all the computational rules when applied in succession.

The Squier complex itself has an involved structure that requires more mathematical tools to describe and understand, and in effect we can use groups to understand group presentations, and structures called ordered groupoids -- also models of symmetry -- to understand inverse semigroup presentations. One important property that we look for is asphericity, which shows that a presentation has an efficient set of rules.  Aspherical group presentations have been studied for a long time, and we know a lot -- but not yet everything -- about them.  Emma's work is currently focussed on how we might extend this study, using ordered groupoids, to inverse monoid presentations.  


In 2014 Emma completed her undergraduate degree at Heriot Watt University, Mathematical, Statistical and Actuarial Sciences BSc (Hons). She graduated with a First and was awarded both the Watt Club Medal and the Roderick McCallum Prize. Emma was also awarded the third year class prize during her degree.

Between her third and fourth years Emma received a Carnegie Trust Undergraduate Vacation Scholarship which allowed her to undertake a research project with her now supervisor Professor Nick Gilbert, which resulted in a co-authored paper published in Semigroup Forum, entitled "Ordered Groupoids and the Holomorph of  an Inverse Semigroup."

Current Carnegie-Caledonian Scholars

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Carnegie PhD Scholarships

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