Guest lectures and seminars - Page 141

Antoine Julien, NTNU, will give a talk with title: Links between cut-and-project tilings and Diophantine approximation

Abstract: Cut-and-project tilings are obtained by cutting a slice of a higher dimensional lattice and projecting it on a lower dimensional space. The result is a point set which is regular enough (since it originates from a lattice), but is not periodic, provided the direction of the slice is irrational in a suitable sense. In one dimension, typical examples of this construction are Sturmian subshifts. It is known that some of their dynamical properties depend on the arithmetic properties of a certain parameter. In this talk, I will recall some known results by Hedlund and Morse on Sturmian subshifts. Then, I will describe how, even in higher dimensions, the repetition properties of some cut-and-project sets can be linked to problems of simultaneous Diophantine approximation. This is joint work with A. Haynes, H. Koivusalo and J. Walton. 

Kristian Ranestad, UiO, gives the Seminar in Algebra and Algebraic Geometry

EPW cubes

Felipe Rincon, UiO, gives the Seminar in Algebra and Algebraic Geometry

Positroids and the totally nonnegative Grassmannian

Audun Mathias Øygard (Master student, Dept. of Mathematics, UiO) will give a seminar in the lunch area, 8th floor N.H. Abel's House at 14:15 September 15th: Measuring similarity of classified advertisements using images and text, with applications to recommendation and search at finn.no