Room 440, Astronomy-Mathematics Building, NTU + Cisco WebEx, Physical+Online Seminar
(實體+線上演講 台灣大學天文數學館440室 + Cisco WebEx)
Zero-one Laws for Random Feasibility Problems
Dylan Altschuler (Carnegie Mellon University)
Abstract
Understanding when a high-dimensional polytope contains integer points is a fundamental problem in a wide variety of fields including combinatorial optimization, computer science, Banach geometry, statistical physics, and information theory. We introduce a general random model of this problem that encodes: the closest vector problem, linear feasibility, integer linear feasibility, perceptron problems, and combinatorial discrepancy in any norm. We study the “margin”, the distance between a polytope and the nearest integer points. The margin acts as a quantitative measure for the "distance to feasibility" for random optimization problems. Our main result is a set of sufficient conditions for the margin to concentrate. Concentration of the margin implies a host of new sharp threshold results in the mentioned models, and also simplifies and extends some key known results.
Meeting number (access code): 2511 553 6422
Meeting password: cwJKy4u6hA3
Organizers: Jhih-Huang Li (NTU), Wai Kit Lam (NTU)