Alistair Stewart

Alistair is lead researcher at Web3 Foundation mainly working on protocol design. Alistair is the architect behind GRANDPA, Polkadot’s novel finality gadget. Moreover, he has worked on the validator selection scheme NPoS and designed Polkadot’s availability and validity scheme.

Research Areas

  • Protocol design, especially consensus

  • Learning theory

  • Stochatsic models

Short Bio. Alistair has been a postdoc in theoretical Computer Science at University of Southern California working with Professor Ilias Diakonikolas, where he worked in learning theory with breakthrough results in high-dimensional robust statistics. Prior to that, in 2015 he obtained a PhD in Informatics from the University of Edinburgh on infinite-state stochastic models. Alistair holds a masters degree in Informatics from the University of Edinburgh and an undergraduate degree from Oxford University.

Selected Publication

  • I. Diakonikolas, G. Kamath, D. Kane, J. Li, A. Moitra, A. Stewart. “Robust Estimators in High Dimensions without the Computational Intractability”, the 57th Annual IEEE Symposium on Foundations of Computer Science (FOCS 2016).

  • I. Diakonikolas, D. Kane, A. Stewart. “The Fourier Transform of Poisson Multinomial Distributions and its Algorithmic Applications”, the 48th Annual ACM Symposium on Theory of Computing (STOC 2016).

  • K. Etessami, A. Stewart, M. Yannakakis. “Polynomial-time Algorithms for Multi-type Branching Processes and Stochastic Context-Free Grammars”, ACM Symposium on Theory of Computing (STOC‘12).