## The many faces of magnitudeAdd to your list(s) Download to your calendar using vCal - Tom Leinster (Edinburgh)
- Wednesday 03 December 2014, 16:00-17:00
- Lecture room A, Watson building.
If you have a question about this talk, please contact Alexandra Tzella. Mathematics Colloquium The magnitude of a square matrix is the sum of all the entries of its inverse. This strange definition, suitably used, produces a family of invariants in different contexts across mathematics. All of them can be loosely understood as “size”. For example, the magnitude of a convex set is an invariant from which one can conjecturally recover many important geometric measures: volume, surface area, perimeter, and so on. The magnitude of a graph is a new invariant that shares features with the Tutte polynomial but is not a specialization of it. The magnitude of a category is very closely related to the Euler characteristic of a topological space. Magnitude also appears in the difficult problem of quantifying biological diversity: under certain circumstances, the greatest possible diversity of an ecosystem is exactly its magnitude. I will give an aerial view of this landscape. This talk is part of the Mathematics Colloquium series. ## This talk is included in these lists:Note that ex-directory lists are not shown. |
## Other listsComputer Science Lunch Time Talk Series Cargo Computer Science Departmental Series## Other talksTBC TBC Quantum simulations using ultra cold ytterbium Extending the Lax type operator for finite W-algebras Ultrafast, all-optical, and highly efficient imaging of molecular chirality Modelling uncertainty in image analysis. |