19–20 Jun 2024
Bosch Budapest Innovation Campus
Europe/Budapest timezone

Computing Classical Partition Functions: From Onsager and Kaufman to Quantum Algorithms

20 Jun 2024, 14:50
20m
Trumpet

Trumpet

Speaker

Roberto Gargiulo

Description

The computation of classical Ising partition functions, coming from statistical physics, is a natural generalization of binary optimization.
This is a notoriously hard problem in general, which makes it an especially interesting task to consider in the search for practical quantum advantage in near term quantum computers.
In this work we view classical Ising models (on certain graphs) as quantum imaginary time evolution, which is enabled by the use of the transfer matrix mapping.
We study this mapping from two points of view: (1) following Onsager and Kaufman's original solution of the 2D Ising model, which serves as a starting point, we consider more general models and the possibility of a similar Lie-theoretic solution; (2) we consider quantum algorithms for the computation of partition functions and thermal averages via transfer matrices, which can be implemented either with block encodings inside larger unitaries or by approximating the state trajectories with unitary operators.

Presentation materials