Archive for the ‘2014’ Category

(CS Colloquium) Michael R. Fellows, The Evolution of the Multivariate Revolution in Algorithmics

Tuesday, February 25th, 2014

FYI (CS Colloquium)

The Evolution of the Multivariate Revolution
in Algorithmics
Michael R. Fellows
Charles Darwin University, Australia
2014/03/24 Monday 4PM – 5:30PM
E3-1 CS Bldg. Room 1501
There has been underway for some decades, with considerable practical consequences, a multivariate revolution in the design of algorithms and the assessment of computational complexity. Parameterized complexity has brought this shift into focus, naming the issues, and offering a multivariate mathematical framework for the central questions that confront the challenge of designing effective algorithms for intrinsically difficult computational problems. Iinternally to this new scientific direction of the central enabling scientific discipline of our time: algorithmics — who lacks a new flood of data? — is a story about how this multivariate revolution has evolved and is still unfolding. The talk will tell the story, in an entertaining way, accessible to students in any field of science that computing serves.

Seung jin Lee, Centrally symmetric polytopes with many faces

Monday, February 24th, 2014
Centrally symmetric polytopes with many faces
Seung jin Lee
KIAS, Seoul
2014/03/17 Monday 4PM-5PM
Room 1409
We study the convex hull of the symmetric moment curve Uk(t)=(cost, sint, cos3t, sin3t, …., cos(2k-1)t, sin(2k-1)t) in R2k and provide deterministic constructions of centrally symmetric polytopes with a record high number faces. In particular, we prove the local neighborliness of the symmetric moment curve, meaning that as long as k distinct points t1, …, tk lie in an arc of a certain length φk > π/2, the points Ut1, …, Utk span a face of the convex hull of Uk(t). In this talk, I will use the local neighborliness of the symmetric moment curve to construct d-dimensional centrally symmetric 2-neighborly polytopes with approximately 3d/2 vertices. This is joint work with Alexander Barvinok and Isabella Novik.