Jason Milionis @tub.

Jason Milionis is kicking off the academic year at tub. with a talk on "Geolocating Block Production with Rational Verifiers". Jason is a Senior Researcher at Category Labs. He got his Ph.D. in Computer Science from Columbia University. His research sits at the crossroads of Algorithmic Game Theory, Economics, and computing. In particular, his interest lies in blockchains, and what they can do as fresh frameworks that come with their own tricky incentive alignment problems. Geographic decentralization is one area where these tricky problems come up. It can improve fault tolerance and help traders incorporate information originating from diverse sources into prices on on-chain exchanges. However, most forms of geolocation of validators do not consider that a validator can replicate its signing key across multiple locations. Jason studies the problem of the geolocation of block production in a model with rational verifiers, allowing block production to span multiple locations. He ties the geolocation of block production to the consensus deadline for proposing a block, and exhibits a challenge-response protocol where each response to every challenger commits to the complete proposal. He reduces any such instance to an instantiation of the signal network model as defined by prior work of Milionis et al. (2025), thereby establishing a signal-truthful equilibrium if verifiers form a convex hull around the feasible set of validator locations. As a result, Jason shows the first protocol with rational verifiers where a proposer that passes verification for its block cannot change its transaction sequence using information originating after the proposal deadline at its claimed location. Drop by: on October 19th at 11h00, in the FAV 2 lecture room, at the TU Informatics faculty (Favoritenstraße 9-11).