Date: March 16, 2026
Time: 3:45-5 p.m.
Location: Computing and Information Science Building, Room 450 or Click here to attend via Zoom
Speaker: Omer Tamuz, CalTech
Abstract: We study agents playing a pure coordination game on a large social network. Agents are restricted to coordinate locally, without access to a global communication device, and so different regions of the network will converge to different actions, precluding perfect coordination. We show that the extent of this inefficiency depends on the network geometry: on some networks, near-perfect efficiency is achievable, while on others welfare is strictly bounded away from the optimum. We provide a geometric condition on the network structure that characterizes when near-efficiency is attainable. On networks in which it is unattainable, our results more generally preclude high correlations between outcomes in a large spectrum of dynamic games. Joint work with Tom Hutchcroft and Olga Rospuskova. See full paper at https://arxiv.org/abs/2602.12571.
Bio: Omar is a professor of economics and mathematics at Caltech. He is interested in probability, dynamics and group theory, and in their applications to topics in microeconomic theory, including information, risk and uncertainty, and social choice. He is a member of the Caltech CSIS interdisciplinary research group, and the chair of Caltech's undergrad admissions committee.
Omar received his B.Sc. in computer science and physics from Tel Aviv University, where he participated in the search for extrasolar planets with Tsevi Mazeh. In 2013 he received his Ph.D. in mathematics from the Weizmann Institute, advised by Elchanan Mossel. From 2013 until 2015, he was a Schramm postdoctoral fellow at the MIT math department / Microsoft Research, where he previously was an intern of Adam Kalai. He has been at Caltech since 2015.