Seminar series
Date
Fri, 02 Mar 2007
16:30
16:30
Location
L2
Speaker
Prof. Angus MacIntyre
Organisation
Queen Mary University, London
Model theory typically looks at classical mathematical structures in novel
ways. The guiding principle is to understand what relations are definable, and
there are usually related questions of effectivity. In the case of Lie theory,
there are two current lines of research, both of which I will describe, but with
more emphasis on the first. The most advanced work concerns exponentials and
logarithms, in both real and complex situations. To understand the definable
relations, and to show various natural problems are decidable, one uses a
mixture of analytic geometry with number-theoretic conjectures related to
Schanuel's Conjecture. More recent work, not yet closely connected to the
preceding, concerns the limit behaviour (model-theoretically), of finite
-dimensional modules over semisimple Lie algebras, and here again, for
decidability, one seems obliged to consider number-theoretic decision problems,
around Siegel's Theorem.