April 10, 2018, 10:15 a.m.
Jakub Tarnawski: "A Constant-Factor Approximation Algorithm for the Asymmetric Traveling Salesman Problem" (STOC 2018 Best Paper)
Title: A Constant-Factor Approximation Algorithm for the Asymmetric Traveling Salesman Problem
Authors: Ola Svensson, Jakub Tarnawski and László Végh
Speaker: Jakub Tarnawski
Time and place: Tuesday, 10th of April 2018, 10:15 am, room 139
We give a constant-factor approximation algorithm for the asymmetric traveling salesman problem. Our approximation guarantee is analyzed with respect to the standard LP relaxation, and thus our result confirms the conjectured constant integrality gap of that relaxation. Our techniques build upon the constant-factor approximation algorithm for the special case of node-weighted metrics. Specifically, we give a generic reduction to structured instances that resemble but are more general than those arising from node-weighted metrics. For those instances, we then solve Local-Connectivity ATSP, a problem known to be equivalent (in terms of constant-factor approximation) to the asymmetric traveling salesman problem. This is joint work with Ola Svensson and László Végh.
(STOC 2018 best paper)