Dr Yemon Choi

Lecturer in Pure Mathematics

Research Interests

The keyword version

Banach and operator algebras. Noncommutative harmonic analysis. Categorical and homological perspectives on functional analysis.

The longer version

I am interested in a range of topics and problems on the interface between algebra and functional analysis. This tends to be driven by particular families of examples, but my preference is for finding general frameworks that unify common features of these examples, once one has investigated individual examples in depth. "Hacking out lots of estimates and then trying to exploit functorial behaviour" is not the most accurate description, nor the most catchy one, but it gives some idea of what I spend my research time doing.In recent years I have worked intensively on various aspects of the Fourier algebras of locally compact groups: studying these objects involves a blend of (non-commutative) harmonic analysis and representation theory. Many of the developments over the last 20 years or so use the tools, or are guided by the philosophy, of the theory of operator spaces and completely bounded maps -- these may be thought of as enriched versions of Banach spaces and linear maps between them, where one allows matricial coefficients and not just scalar ones.

I am also interested in algebras of convolution operators arising from the canonical representation(s) of a group G on the Banach space Lp(G). When p=2 there is a rich theory available, from the world of C*-algebras and von Neumann algebras; for other values of p many basic structural questions remain unresolved, even for very explicit examples such as G=SLn(R) or SLn(Z).