About Me
Hi! My name is Ivan and I’m an assistant professor at Utrecht University. I’m especially interested in (Algorithmic) Game Theory, Algorithms, Cryptography, Complexity and Distributed Systems. I’m also passionate about engaging young students in STEM. In my spare time I like to exercise, play the ukulele, work on my personal projects, or play soccer, board games or videogames.
Publications
Receiver-Oriented Cheap Talk Design
I. Arieli, I. Geffner and M. Tennenholtz
In Preparation – 2024 (PDF)
Strengthening Nash Equilibria
I. Geffner and M. Tennenholtz
2023 (arXiv)
The Value of Mediation in Long Cheap Talk
I. Arieli, I. Geffner and M. Tennenholtz
2023 (arXiv)
Communication games, sequential equilibrium, and mediators
I. Geffner and J. Y. Halpern
Under Review – 2023 (arXiv)
Bounding the communication complexity of fault-tolerant common coin tossing
I. Geffner and J. Y. Halpern
Under Review – 2023 (arXiv)
Resilient Information Aggregation
I. Arieli, I. Geffner and M. Tennenholtz
TARK 2023 (arXiv)
Mediated Cheap Talk Design
I. Arieli, I. Geffner and M. Tennenholtz
AAAI 2023 (arXiv)
Lower Bounds on Implementing Mediators in Asynchronous Systems
I. Geffner and J. Y. Halpern
JACM 2022 (link)
Implementing Mediators with Cheap Talk (Dissertation)
I. Geffner
2021 (link)
Security in Asynchronous Interactive Systems
I. Geffner and J. Y. Halpern
SSS 2021 (arXiv)
Implementing Mediators with Asynchronous Cheap Talk
I. Abraham, D.Dolev, I. Geffner and J. Y. Halpern
PODC 2019 (conference, arXiv)
Counting Outerplanar Maps
I. Geffner and M. Noy
Electronic Journal of Combinatorics, 2017 (link)
Projects
AI Coliseum (co-founder, developer) : A non-profit online platform that organizes programming competitions focused on implementing Artificial Intelligences for different games.
Taller Programa (organizer, instructor): An open programming course for high school students in Barcelona.
Taller Demostra (organizer, instructor): An open course for high school students in Barcelona that want to go beyond the Math taught at school.
CV
You can check my CV here.