Discrete Applied Mathematics Seminar by Emily Barnard: Dynamics and Topology of Lattice Posets Related to the Weak Order

Speaker: Emily Barnard, DePaul University, 

Title: Dynamics and Topology of Lattice Posets Related to the Weak Order

Abstract: In this talk, I will highlight results from three recent research projects done in collaboration with undergraduate students at DePaul. The unifying theme in all of them is the combinatorics of permutations and the weak order on S_n. We will begin by describing a relatively new object from dynamical combinatorics called the pop-stack sorting method. The pop-stack sorting method sorts a permutation by reversing each descending run in the permutation without changing their relative position. In collaboration with Juarez, Rodriguez, Rojas, and Taylor, we extend the pop-stack sorting method to the poset of maximal tubings. We then explore the size of various forward orbits of the pop-stack sorting method for maximal tubings of the cycle graph. This talk will be accessible to all --- undergraduate students interested in discrete math or combinatorics are welcome to attend.

 

 

Discrete Applied Math Seminar