Wednesday, April 23, 2025 - 4:00pm
Event Calendar Category
Other LIDS Events
Speaker Name
James Saunderson
Affiliation
Monash University
Building and Room number
32-144
"Optimizing Quantum Relative Entropies"
Quantum relative entropies are jointly convex functions of two positive definite matrices that arise naturally in quantum information theory and generalize classical notions of divergence between probability distributions. Establishing the convexity properties of these functions is typically quite non-trivial. Exploiting these properties algorithmically is, similarly, a challenge.
In this talk, I will discuss some of the mathematical ingredients in the interior-point solver QICS (qics.dev), for solving convex optimization problems involving quantum relative entropies. The focus will be on describing a powerful method to prove self-concordance of barrier functions related to various quantum relative entropies. If time permits, I’ll touch on examples of problem structures — naturally arising in some quantum information applications — that, when present, can be exploited to speed up a generic interior point method.
Based on joint work with Hamza Fawzi (Cambridge) and Kerry He (Monash).
James Saunderson is a Senior Lecturer in the Department of Electrical and Computer Systems Engineering at Monash University. He received a PhD in Electrical Engineering and Computer Science from MIT in 2015, and undergraduate degrees in Mathematics and Electrical Engineering from the University of Melbourne in 2008. With Hamza Fawzi and Pablo Parrilo, he was awarded the 2020 SIAM Activity Group on Optimization Best Paper Prize, and was the recipient of an Australian Research Council Discovery Early-Career Researcher Award (DECRA). His research interests lie in mathematical optimization and its applications.